Data storage system utilizing proxy device for storage operations

ABSTRACT

A data storage environment can include a secondary storage computing device that acts as a proxy for other secondary storage computing devices. For example, the secondary storage computing device receives a storage operation request from one or more of the other secondary storage computing devices, such as a request to create a snapshot of client data. The secondary storage computing device generally acts as an intermediary between the other secondary storage computing devices and the storage device to carry out the snapshots or other storage operations. The secondary storage computing device may further receive a notification upon completion of the storage operations, and transmit relevant data to the requesting secondary storage computing device regarding the storage operation.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/134,440, filed Dec. 19, 2013, which claims priority benefitto U.S. Prov. App. No. 61/740,370, filed Dec. 20, 2012, and is acontinuation-in-part of U.S. application Ser. No. 13/787,609, filed Mar.6, 2013, now U.S. Pat. No. 9,298,715, issued Mar. 29, 2016, which claimspriority benefit to U.S. Prov. App. No. 61/607,728, filed Mar. 7, 2012,each of which is hereby incorporated herein by reference in itsentirety.

BACKGROUND

Businesses worldwide recognize the commercial value of their data andseek reliable, cost-effective ways to protect the information stored ontheir computer networks while minimizing impact on productivity.Protecting information is often part of a routine process that isperformed within an organization.

A company might back up critical computing systems such as databases,file servers, web servers, and so on as part of a daily, weekly, ormonthly maintenance schedule. The company may similarly protectcomputing systems used by each of its employees, such as those used byan accounting department, marketing department, engineering department,and so forth.

Given the rapidly expanding volume of data under management, companiesalso continue to seek innovative techniques for managing data growth, inaddition to protecting data. For instance, companies often implementmigration techniques for moving data to lower cost storage over time anddata reduction techniques for reducing redundant data, pruning lowerpriority data, etc.

Enterprises also increasingly view their stored data as a valuableasset. Along these lines, customers are looking for solutions that notonly protect and manage, but also leverage their data. For instance,solutions providing data analysis capabilities, improved datapresentation and access features, and the like, are in increasingdemand.

SUMMARY

Security criteria for interacting with storage arrays can vary acrossvendors and product lines. For instance, some vendors may specify that acertain limited number of media agents or other components can beauthorized to directly interact with the array in order to limitunauthorized access and otherwise preserve data security. However, inmany data storage environments a single storage array or group ofstorage arrays are used to store and manage data generated by arelatively large number of client computing devices or other sources.Moreover, it is desirable for a data storage solution to be compatiblewith a large number of storage products provided by different vendors.

In order to address these and other challenges, a data storage systemaccording to certain embodiments designates a particular media agent (orother appropriate component) or group thereof to act as a centralizedproxy to communicate directly with a storage device for performingcertain storage operations (e.g., hardware snapshot operations) ofclient data sets. In this manner, the systems and methods describedherein can provide efficient, straightforward integration of a varietyof storage products provided by different vendors. For instance, thetechniques described herein are compatible with the following storageproducts, without limitation: EMC Clariion, EMC Symmetrix, EMC Celerra,Dell EqualLogic, IBM XIV, NetApp FAS, and HP EVA, and HP 3PAR diskarrays.

In some embodiments, a method for performing a storage operation using aproxy secondary storage computing device is provided. In certainembodiments, the method includes receiving at a first computing device arequest to perform a storage operation from a second computing device.In some embodiments, the first computing device and the second secondarystorage computing device form part of a networked storage systemcomprising at least one storage device that is capable of performing thestorage operation. The method can further include forwarding, using thefirst computing device, the storage operation request to the storagedevice on behalf of the second computing device. In certain embodiments,the storage device performs the storage operation in response to receiptof the storage operation request. The method can further includereceiving, at the first computing device, an identifier associated withthe performed storage operation, and forwarding the identifier to thesecond computing device.

In some embodiments, the second secondary storage computing deviceforwards the identifier to a client computing device. In certainembodiments, the second secondary storage computing device communicatesdirectly with the storage device for a first set of storage operationsand communicates with the storage device via the first secondary storagedevice for a second set of storage operations. In some embodiments, thefirst set of storage operations comprises reading data from the storagedevice and the second set of storage operations comprises performing asnapshot of data residing on a client computing device.

In certain embodiments, the second secondary storage computing device isnot in direct communication with the storage device and is only inindirect communication with the storage device via the first secondarystorage computing device. In some embodiments, the second secondarystorage computing device does not have direct access to the storagedevice and only indirectly accesses the storage device via the firstsecondary storage computing device. In certain embodiments, the methodfurther includes receiving storage operation requests from a pluralityof other secondary storage computing devices, and forwarding the storageoperation requests to the storage device.

In some embodiments, the storage operation request comprises a requestto perform a snapshot of data residing in a client computing deviceassociated with the second secondary storage computing device. Incertain embodiments, the first secondary storage computing deviceauthenticates with the storage device prior to forwarding the storageoperations request to the storage device.

In certain embodiments, a data storage system is described that includesa storage device configured to perform snapshot operations on dataresiding on the storage device, and a first computing device incommunication with a second computing device, a third computing device,and the storage device. In some embodiments, the first computing devicecan be configured to receive a storage operation request device from thesecond secondary storage computing device, and forward, using the firstsecondary storage computing device, the storage operation request to thestorage device on behalf of the second secondary storage computingdevice. In certain embodiments, the storage device performs the storageoperation, receives an identifier associated with the performed storageoperation, and forwards the identifier to the second secondary storagecomputing device.

In some embodiments, the second secondary storage computing deviceforwards the identifier to a client computing device. In certainembodiments, the second secondary storage computing device is configuredto communicate directly with the storage device for a first set ofstorage operations and communicate with the storage device via the firstsecondary storage device for a second set of storage operations. In someembodiments, the first set of storage operations comprises reading datafrom the storage device and the second set of storage operationscomprises performing a snapshot of data residing on a client computingdevice.

In certain embodiments, the second secondary storage computing device isnot in direct communication with the storage device and is only inindirect communication with the storage device via the first secondarystorage computing device. In some embodiments, wherein the secondsecondary storage computing device does not have direct access to thestorage device and only indirectly accesses the storage device via thefirst secondary storage computing device. In certain embodiments, thefirst secondary storage computing device is further configured toreceive storage operation requests from a plurality of other secondarystorage computing devices and forward the storage operation requests tothe storage device.

In some embodiments, the storage operation request comprises a requestto perform a snapshot of data residing in a client computing deviceassociated with the second secondary storage computing device. Incertain embodiments, the first secondary storage computing deviceauthenticates with the storage device prior to forwarding the storageoperations request. In some embodiments, the requested storage operationcomprises a snapshot operation. In certain embodiments, the requestedstorage operation comprises an archive operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram illustrating an exemplary informationmanagement system.

FIG. 1B is a detailed view of a primary storage device, a secondarystorage device, and some examples of primary data and secondary copydata.

FIG. 1C is a block diagram of an exemplary information management systemincluding a storage manager, one or more data agents, and one or moremedia agents.

FIG. 1D is a block diagram illustrating a scalable informationmanagement system.

FIG. 1E illustrates certain secondary copy operations according to anexemplary storage policy.

FIGS. 2A-2C are block diagrams illustrative of embodiments of a storagenetwork environment including a proxy client communicating with astorage device on behalf of a client.

FIGS. 3A and 3B are state diagrams illustrative of the interactionbetween the various components of the storage network environment ofFIG. 2A.

FIGS. 4-7 are flow diagrams illustrative of embodiments of routinesimplemented by a client proxy for requesting a storage device to performone or more storage operations on behalf of a client.

FIG. 8 is a block diagram illustrative of an embodiment of a storagenetwork environment including a proxy media agent communicating with astorage device to carry out storage operations on client data.

FIG. 9 is a state diagram illustrative of example interaction betweenthe various components of the storage network environment of FIG. 8.

FIG. 10 is a flow diagram illustrative of embodiments of a routineimplemented by a proxy media agent for requesting a storage device toperform one or more storage operations on client data.

DETAILED DESCRIPTION

Generally described, the present disclosure is directed to a system,method, and computer readable non-transitory storage medium for astorage management system. Specifically, embodiments described hereininclude systems and methods to perform storage operations on client datausing a proxy device, such as one or more media agents or othercomponents.

As indicated above, a data storage system according to certainembodiments designates a particular media agent (or other appropriatecomponent) or group thereof to act as a centralized proxy to communicatedirectly with a storage device for performing certain storage operations(e.g., hardware snapshot operations) of client data sets. For instance,in some cases requests to perform storage operations are routed througha proxy media agent, which interfaces with storage media. The storagemedia in some embodiments comprises a storage array capable of creatingand maintaining snapshots (e.g., hardware snapshots) of primary copydata (e.g., production or “live” copies of client data). In some cases,the proxy media agent can directly communicate with the storage media toimplement control functionality, such as by authorizing andauthenticating access to the storage media, communicating the request tothe storage media, receiving completion and other information regardingthe operation, and the like.

As an example, and not to be construed as limiting, the storage managercan contain a storage policy that determines how frequently a snapshotis taken of a particular set of client data. Based on the storagepolicy, the storage manager instructs the client to initiate thesnapshot operation. The storage manager may further instruct a firstmedia agent residing on or otherwise associated with the client tocoordinate the snapshot operation. Rather than interacting directly withthe storage device, the first media agent communicates with a proxymedia agent, which in turn interacts with the storage media to initiatethe storage operation. For instance, the proxy media agent canauthenticate with and transmit the storage operation request to thestorage device.

The storage device performs the requested snapshot operation andnotifies the proxy media agent upon completion. The notification caninclude, but is not limited to a snapshot identifier, a disk arrayidentifier, creation time, or other information related to the snapshot.Upon receiving the notification from the storage device, the proxy mediaagent transmits relevant data to the first media agent and therequesting client. The client can then notify the storage manager thatthe storage operation has been completed. The storage operations caninclude, but are not limited to a snapshot creation, mount, revert,destroy, unmount, unmap, etc.

Further examples of systems and methods for performing storageoperations using a centralized proxy component are shown and describedbelow with respect to FIGS. 7-9, for example.

In addition, embodiments described herein include systems and methodsfor servicing requests to perform storage on client data, where multipleclients share underlying storage media. The requests, as well as theresults of the storage operations, are routed through a proxy, whichinterfaces with the storage media. The proxy may be a physical host in avirtualized computing environment or may be implemented on a host in avirtualized computing environment. And the clients may be physicalclients, or virtual clients instantiated on the host. In other cases,the proxy and the clients are implemented on separate computing devices.Furthermore, the clients may not have direct access to the hardwarearray or other storage device. In some embodiments, for example, theclients cannot perform one or more types of storage operations (e.g.,snapshot operations) without the aid of the proxy. In some embodiments,the clients only communicate with and/or access the storage device viathe proxy.

As an example, and not to be construed as limiting, the storage managercan contain a storage policy that determines how frequently a snapshotis taken of the client and the proxy client, how and when data is to bereverted, etc. Based on the storage policy, the storage managertransmits a storage operation request to the client. The client,recognizing that it is unable to perform the storage operation request,requests that the proxy client perform the storage operation request.The proxy client receives the storage operation request and identifiesthe portions of hardware storage that contain the data associated withthe client. The proxy client then transmits the storage operationrequest to the storage device, specifying the portions of hardwarestorage that contain the data associated with the client.

The storage device performs the requested storage operation on thespecified portions of hardware storage and notifies the proxy clientupon completion. The notification can include, but is not limited to asnapshot identifier, a disk array identifier, or other informationrelated to the snapshot. Upon receiving the notification from thestorage device, the proxy client transmits relevant data to the client.The client can then notify the storage manager that the storageoperation has been completed.

In some embodiments, the storage operation is a snapshot creation.Accordingly, the storage manager transmits a snapshot command based on astorage policy to the client. Upon receiving the command and determiningthat the client is unable to create the snapshot, the client transmits asnapshot creation request to the proxy client. The client identifies theportions of physical storage in the disk array that contain the dataassociated with the client. The proxy client transmits the snapshotcreation request to the storage device, identifying the portions ofphysical storage in the disk array that are to form part of thesnapshot. Upon creating the snapshot, the storage device transmits tothe client a snapshot identifier, and other information. For example,the storage device can transmit a volume snap identifier, a groupidentifier, the status of the device, creation time, and/or an arrayidentifier. The proxy client transmits a snapshot identifier to theclient, and the client notifies the storage manager that the snapshothas been created.

In certain embodiments the storage operation can be a mount or read of asnapshot. In such an embodiment the storage manager transmits amount/read command of a particular snapshot to the client. Uponreceiving the command, the client determines whether the client is ableto mount the particular snapshot. If the client does not have access tothe storage device or is otherwise unable to mount the particularsnapshot directly, the client requests the proxy client to map theportions of the storage device that contain the snapshot data to theclient. In the request, the client can include the snapshot identifier.The proxy client communicates with the storage device to identify theportions of physical storage in the disk array that contain the dataassociated with the client, including the particular snapshot. The proxyclient requests location identifying information of the portions ofphysical storage from the disk array that contain the particularsnapshot, and the storage device retrieves the location identifyinginformation, or snapshot disk data. The proxy client in turn transmitsthe snapshot disk data to the client. Upon receiving the snapshotlocation information and/or disk data, the client can mount the snapshotand notify the storage manager of the completion of the mounting. Oncemounted, the client can access the snap mounted disk directly.

In some embodiments, the storage operation is a snapshot revertoperation, where the snapshot is accessed to revert the virtual clientdata store back to the state it was in at the time the snapshot wastaken. In such an embodiment, the storage manager transmits a revertcommand to the client to revert to a specified snapshot. The clientdetermines that it cannot perform the revert operation alone andtransmits the reversion request to the proxy client, such as the agentof the proxy client. The reversion request can include informationuniquely identifying the specified snapshot, such as locationinformation, other disk data and/or a snapshot identifier, etc. Theproxy client transmits the request for the reversion to the storagedevice. The storage device uses the information received from the proxyclient to revert to an earlier snapshot version of the data related tothe requesting client. Once the storage device has completed thereversion, the storage device notifies the proxy client and the proxyclient notifies the client. In turn, the client notifies the storagemanager of the completion of the reversion.

Information Management System Overview

With the increasing importance of protecting and leveraging data,organizations simply cannot afford to take the risk of losing criticaldata. Moreover, runaway data growth and other modern realities makeprotecting and managing data an increasingly difficult task. There istherefore a need for efficient, powerful, and user-friendly solutionsfor protecting and managing data.

Depending on the size of the organization, there are typically many dataproduction sources which are under the purview of tens, hundreds, oreven thousands of employees or other individuals. In the past,individual employees were sometimes responsible for managing andprotecting their data. A patchwork of hardware and software pointsolutions have been applied in other cases. These solutions were oftenprovided by different vendors and had limited or no interoperability.

Certain embodiments described herein provide systems and methods capableof addressing these and other shortcomings of prior approaches byimplementing unified, organization-wide information management. FIG. 1Ashows one such information management system 100, which generallyincludes combinations of hardware and software configured to protect andmanage data and metadata generated and used by the various computingdevices in the information management system 100.

The organization which employs the information management system 100 maybe a corporation or other business entity, non-profit organization,educational institution, household, governmental agency, or the like.

Generally, the systems and associated components described herein may becompatible with and/or provide some or all of the functionality of thesystems and corresponding components described in one or more of thefollowing U.S. patents and patent application publications assigned toCommVault Systems, Inc., each of which is hereby incorporated in itsentirety by reference herein:

-   -   U.S. Pat. Pub. No. 2010-0332456, entitled “DATA OBJECT STORE AND        SERVER FOR A CLOUD STORAGE ENVIRONMENT, INCLUDING DATA        DEDUPLICATION AND DATA MANAGEMENT ACROSS MULTIPLE CLOUD STORAGE        SITES”;    -   U.S. Pat. No. 7,035,880, entitled “MODULAR BACKUP AND RETRIEVAL        SYSTEM USED IN CONJUNCTION WITH A STORAGE AREA NETWORK”;    -   U.S. Pat. No. 7,343,453, entitled “HIERARCHICAL SYSTEMS AND        METHODS FOR PROVIDING A UNIFIED VIEW OF STORAGE INFORMATION”;    -   U.S. Pat. No. 7,395,282, entitled “HIERARCHICAL BACKUP AND        RETRIEVAL SYSTEM”;    -   U.S. Pat. No. 7,246,207, entitled “SYSTEM AND METHOD FOR        DYNAMICALLY PERFORMING STORAGE OPERATIONS IN A COMPUTER        NETWORK”;    -   U.S. Pat. No. 7,747,579, entitled “METABASE FOR FACILITATING        DATA CLASSIFICATION”;    -   U.S. Pat. No. 8,229,954, entitled “MANAGING COPIES OF DATA”;    -   U.S. Pat. No. 7,617,262, entitled “SYSTEM AND METHODS FOR        MONITORING APPLICATION DATA IN A DATA REPLICATION SYSTEM”;    -   U.S. Pat. No. 7,529,782, entitled “SYSTEM AND METHODS FOR        PERFORMING A SNAPSHOT AND FOR RESTORING DATA”;    -   U.S. Pat. No. 8,230,195, entitled “SYSTEM AND METHOD FOR        PERFORMING AUXILIARY STORAGE OPERATIONS”;    -   U.S. Pat. Pub. No. 2012/0084269, entitled “CONTENT-ALIGNED,        BLOCK-BASED DEDUPLICATION”;    -   U.S. Pat. Pub. No. 2006/0224846, entitled “SYSTEM AND METHOD TO        SUPPORT SINGLE INSTANCE STORAGE OPERATIONS”;    -   U.S. Pat. Pub. No. 2009/0329534, entitled “APPLICATION-AWARE AND        REMOTE SINGLE INSTANCE DATA MANAGEMENT”;    -   U.S. Pat. Pub. No. 2012/0150826, entitled “DISTRIBUTED        DEDUPLICATED STORAGE SYSTEM”;    -   U.S. Pat. Pub. No. 2012/0150818, entitled “CLIENT-SIDE        REPOSITORY IN A NETWORKED DEDUPLICATED STORAGE SYSTEM”;    -   U.S. Pat. No. 8,170,995, entitled “METHOD AND SYSTEM FOR OFFLINE        INDEXING OF CONTENT AND CLASSIFYING STORED DATA”; and    -   U.S. Pat. No. 8,156,086, entitled “SYSTEMS AND METHODS FOR        STORED DATA VERIFICATION”.

The illustrated information management system 100 includes one or moreclient computing device 102 having at least one application 110executing thereon, and one or more primary storage devices 104 storingprimary data 112. The client computing device(s) 102 and the primarystorage devices 104 may generally be referred to in some cases as aprimary storage subsystem 117.

Depending on the context, the term “information management system” canrefer to generally all of the illustrated hardware and softwarecomponents. Or, in other instances, the term may refer to only a subsetof the illustrated components.

For instance, in some cases information management system 100 generallyrefers to a combination of specialized components used to protect, move,manage, manipulate and/or process data and metadata generated by theclient computing devices 102. However, the term may generally not referto the underlying components that generate and/or store the primary data112, such as the client computing devices 102 themselves, theapplications 110 and operating system residing on the client computingdevices 102, and the primary storage devices 104.

As an example, “information management system” may sometimes refer onlyto one or more of the following components and corresponding datastructures: storage managers, data agents, and media agents. Thesecomponents will be described in further detail below.

Client Computing Devices

There are typically a variety of sources in an organization that producedata to be protected and managed. As just one illustrative example, in acorporate environment such data sources can be employee workstations andcompany servers such as a mail server, a web server, or the like. In theinformation management system 100, the data generation sources includethe one or more client computing devices 102.

The client computing devices 102 may include, without limitation, one ormore: workstations, personal computers, desktop computers, or othertypes of generally fixed computing systems such as mainframe computersand minicomputers.

The client computing devices 102 can also include mobile or portablecomputing devices, such as one or more laptops, tablet computers,personal data assistants, mobile phones (such as smartphones), and othermobile or portable computing devices such as embedded computers, set topboxes, vehicle-mounted devices, wearable computers, etc.

In some cases, each client computing device 102 is associated with oneor more users and/or corresponding user accounts, of employees or otherindividuals.

The term “client computing device” is used herein because theinformation management system 100 generally “serves” the data managementand protection needs for the data generated by the client computingdevices 102. However, the use of this term does not imply that theclient computing devices 102 cannot be “servers” in other respects. Forinstance, a particular client computing device 102 may act as a serverwith respect to other devices, such as other client computing devices102. As just a few examples, the client computing devices 102 caninclude mail servers, file servers, database servers, and web servers.

The client computing devices 102 may additionally include virtualizedand/or cloud computing resources. For instance, one or more virtualmachines may be provided to the organization by a third-party cloudservice vendor. Or, in some embodiments, the client computing devices102 include one or more virtual machine(s) running on a virtual machinehost computing device operated by the organization. As one example, theorganization may use one virtual machine as a database server andanother virtual machine as a mail server. A virtual machine manager(VMM) (e.g., a Hypervisor) may manage the virtual machines, and resideand execute on the virtual machine host computing device.

Each client computing device 102 may have one or more applications 110(e.g., software applications) executing thereon which generate andmanipulate the data that is to be protected from loss.

The applications 110 generally facilitate the operations of anorganization (or multiple affiliated organizations), and can include,without limitation, mail server applications (e.g., Microsoft ExchangeServer), file server applications, mail client applications (e.g.,Microsoft Exchange Client), database applications (e.g., SQL, Oracle,SAP, Lotus Notes Database), word processing applications (e.g.,Microsoft Word), spreadsheet applications, financial applications,presentation applications, browser applications, mobile applications,entertainment applications, and so on.

The applications 110 can include at least one operating system (e.g.,Microsoft Windows, Mac OS X, iOS, IBM z/OS, Linux, other Unix-basedoperating systems, etc.), which may support one or more file systems andhost the other applications 110.

As shown, the client computing devices 102 and other components in theinformation management system 100 can be connected to one another viaone or more communication pathways 114. The communication pathways 114can include one or more networks or other connection types including asany of following, without limitation: the Internet, a wide area network(WAN), a local area network (LAN), a Storage Area Network (SAN), a FibreChannel connection, a Small Computer System Interface (SCSI) connection,a virtual private network (VPN), a token ring or TCP/IP based network,an intranet network, a point-to-point link, a cellular network, awireless data transmission system, a two-way cable system, aninteractive kiosk network, a satellite network, a broadband network, abaseband network, other appropriate wired, wireless, or partiallywired/wireless computer or telecommunications networks, combinations ofthe same or the like. The communication pathways 114 in some cases mayalso include application programming interfaces (APIs) including, e.g.,cloud service provider APIs, virtual machine management APIs, and hostedservice provider APIs.

Primary Data and Exemplary Primary Storage Devices

Primary data 112 according to some embodiments is production data orother “live” data generated by the operating system and otherapplications 110 residing on a client computing device 102. The primarydata 112 is stored on the primary storage device(s) 104 and is organizedvia a file system supported by the client computing device 102. Forinstance, the client computing device(s) 102 and correspondingapplications 110 may create, access, modify, write, delete, andotherwise use primary data 112.

Primary data 112 is generally in the native format of the sourceapplication 110. According to certain aspects, primary data 112 is aninitial or first (e.g., created before any other copies or before atleast one other copy) stored copy of data generated by the sourceapplication 110. Primary data 112 in some cases is created substantiallydirectly from data generated by the corresponding source applications110.

The primary data 112 may sometimes be referred to as a “primary copy” inthe sense that it is a discrete set of data. However, the use of thisterm does not necessarily imply that the “primary copy” is a copy in thesense that it was copied or otherwise derived from another storedversion.

The primary storage devices 104 storing the primary data 112 may berelatively fast and/or expensive (e.g., a disk drive, a hard-disk array,solid state memory, etc.). In addition, primary data 112 may be intendedfor relatively short term retention (e.g., several hours, days, orweeks).

According to some embodiments, the client computing device 102 canaccess primary data 112 from the primary storage device 104 by makingconventional file system calls via the operating system. Primary data112 representing files may include structured data (e.g., databasefiles), unstructured data (e.g., documents), and/or semi-structureddata. Some specific examples are described below with respect to FIG.1B.

It can be useful in performing certain tasks to break the primary data112 up into units of different granularities. In general, primary data112 can include files, directories, file system volumes, data blocks,extents, or any other types or granularities of data objects. As usedherein, a “data object” can refer to both (1) any file that is currentlyaddressable by a file system or that was previously addressable by thefile system (e.g., an archive file) and (2) a subset of such a file.

As will be described in further detail, it can also be useful inperforming certain functions of the information management system 100 toaccess and modify metadata within the primary data 112. Metadatagenerally includes information about data objects or characteristicsassociated with the data objects.

Metadata can include, without limitation, one or more of the following:the data owner (e.g., the client or user that generates the data), thelast modified time (e.g., the time of the most recent modification ofthe data object), a data object name (e.g., a file name), a data objectsize (e.g., a number of bytes of data), information about the content(e.g., an indication as to the existence of a particular search term),to/from information for email (e.g., an email sender, recipient, etc.),creation date, file type (e.g., format or application type), lastaccessed time, application type (e.g., type of application thatgenerated the data object), location/network (e.g., a current, past orfuture location of the data object and network pathways to/from the dataobject), frequency of change (e.g., a period in which the data object ismodified), business unit (e.g., a group or department that generates,manages or is otherwise associated with the data object), and aginginformation (e.g., a schedule, such as a time period, in which the dataobject is migrated to secondary or long term storage), boot sectors,partition layouts, file location within a file folder directorystructure, user permissions, owners, groups, access control lists[ACLs]), system metadata (e.g., registry information), combinations ofthe same or the like.

In addition to metadata generated by or related to file systems andoperating systems, some of the applications 110 maintain indices ofmetadata for data objects, e.g., metadata associated with individualemail messages. Thus, each data object may be associated withcorresponding metadata. The use of metadata to perform classificationand other functions is described in greater detail below.

Each of the client computing devices 102 are associated with and/or incommunication with one or more of the primary storage devices 104storing corresponding primary data 112. A client computing device 102may be considered to be “associated with” or “in communication with” aprimary storage device 104 if it is capable of one or more of: storingdata to the primary storage device 104, retrieving data from the primarystorage device 104, and modifying data retrieved from a primary storagedevice 104.

The primary storage devices 104 can include, without limitation, diskdrives, hard-disk arrays, semiconductor memory (e.g., solid statedrives), and network attached storage (NAS) devices. In some cases, theprimary storage devices 104 form part of a distributed file system. Theprimary storage devices 104 may have relatively fast I/O times and/orare relatively expensive in comparison to the secondary storage devices108. For example, the information management system 100 may generallyregularly access data and metadata stored on primary storage devices104, whereas data and metadata stored on the secondary storage devices108 is accessed relatively less frequently.

In some cases, each primary storage device 104 is dedicated to anassociated client computing devices 102. For instance, a primary storagedevice 104 in one embodiment is a local disk drive of a correspondingclient computing device 102. In other cases, one or more primary storagedevices 104 can be shared by multiple client computing devices 102. Asone example, a primary storage device 104 can be a disk array shared bya group of client computing devices 102, such as one of the followingtypes of disk arrays: EMC Clariion, EMC Symmetrix, EMC Celerra, DellEqualLogic, IBM XIV, NetApp FAS, HP EVA, and HP 3PAR.

The information management system 100 may also include hosted services(not shown), which may be hosted in some cases by an entity other thanthe organization that employs the other components of the informationmanagement system 100. For instance, the hosted services may be providedby various online service providers to the organization. Such serviceproviders can provide services including social networking services,hosted email services, or hosted productivity applications or otherhosted applications).

Hosted services may include software-as-a-service (SaaS),platform-as-a-service (PaaS), application service providers (ASPs),cloud services, or other mechanisms for delivering functionality via anetwork. As it provides services to users, each hosted service maygenerate additional data and metadata under management of theinformation management system 100, e.g., as primary data 112. In somecases, the hosted services may be accessed using one of the applications110. As an example, a hosted mail service may be accessed via browserrunning on a client computing device 102.

Secondary Copies and Exemplary Secondary Storage Devices

The primary data 112 stored on the primary storage devices 104 may becompromised in some cases, such as when an employee deliberately oraccidentally deletes or overwrites primary data 112 during their normalcourse of work. Or the primary storage devices 104 can be damaged orotherwise corrupted.

For recovery and/or regulatory compliance purposes, it is thereforeuseful to generate copies of the primary data 112. Accordingly, theinformation management system 100 includes one or more secondary storagecomputing devices 106 and one or more secondary storage devices 108configured to create and store one or more secondary copies 116 of theprimary data 112 and associated metadata. The secondary storagecomputing devices 106 and the secondary storage devices 108 may bereferred to in some cases as a secondary storage subsystem 118.

Creation of secondary copies 116 can help meet information managementgoals, such as: restoring data and/or metadata if an original version(e.g., of primary data 112) is lost (e.g., by deletion, corruption, ordisaster); allowing point-in-time recovery; complying with regulatorydata retention and electronic discovery (e-discovery) requirements;reducing utilized storage capacity; facilitating organization and searchof data; improving user access to data files across multiple computingdevices and/or hosted services; and implementing data retentionpolicies.

Types of secondary copy operations can include, without limitation,backup operations, archive operations, snapshot operations, replicationoperations (e.g., continuous data replication [CDR]), data retentionpolicies such as or information lifecycle management and hierarchicalstorage management operations, and the like. These specific typesoperations are discussed in greater detail below.

Regardless of the type of secondary copy operation, the client computingdevices 102 access or receive primary data 112 and communicate the data,e.g., over the communication pathways 114, for storage in the secondarystorage device(s) 108.

A secondary copy 116 can comprise a separate stored copy of applicationdata that is derived from one or more earlier created, stored copies(e.g., derived from primary data 112 or another secondary copy 116).Secondary copies 116 can include point-in-time data, and may be intendedfor relatively long-term retention (e.g., weeks, months or years),before some or all of the data is moved to other storage or isdiscarded.

In some cases, a secondary copy 116 is a copy of application datacreated and stored subsequent to at least one other stored instance(e.g., subsequent to corresponding primary data 112 or to anothersecondary copy 116), in a different storage device than at least oneprevious stored copy, and/or remotely from at least one previous storedcopy. Secondary copies 116 may be stored in relatively slow and/or lowcost storage (e.g., magnetic tape). A secondary copy 116 may be storedin a backup or archive format, or in some other format different thanthe native source application format or other primary data format.

In some cases, secondary copies 116 are indexed so users can browse andrestore at another point in time. After creation of a secondary copy 116representative of certain primary data 112, a pointer or other locationindicia (e.g., a stub) may be placed in primary data 112, or beotherwise associated with primary data 112 to indicate the currentlocation on the secondary storage device(s) 108.

Since an instance a data object or metadata in primary data 112 maychange over time as it is modified by an application 110 (or hostedservice or the operating system), the information management system 100may create and manage multiple secondary copies 116 of a particular dataobject or metadata, each representing the state of the data object inprimary data 112 at a particular point in time. Moreover, since aninstance of a data object in primary data 112 may eventually be deletedfrom the primary storage device 104 and the file system, the informationmanagement system 100 may continue to manage point-in-timerepresentations of that data object, even though the instance in primarydata 112 no longer exists.

For virtualized computing devices the operating system and otherapplications 110 of the client computing device(s) 102 may executewithin or under the management of virtualization software (e.g., a VMM),and the primary storage device(s) 104 may comprise a virtual diskcreated on a physical storage device. The information management system100 may create secondary copies 116 of the files or other data objectsin a virtual disk file and/or secondary copies 116 of the entire virtualdisk file itself (e.g., of an entire .vmdk file).

Secondary copies 116 may be distinguished from corresponding primarydata 112 in a variety of ways, some of which will now be described.First, as discussed, secondary copies 116 can be stored in a differentformat (e.g., backup, archive, or other non-native format) than primarydata 112. For this or other reasons, secondary copies 116 may not bedirectly useable by the applications 110 of the client computing device102, e.g., via standard system calls or otherwise without modification,processing, or other intervention by the information management system100.

Secondary copies 116 are also often stored on a secondary storage device108 that is inaccessible to the applications 110 running on the clientcomputing devices 102 (and/or hosted services). Some secondary copies116 may be “offline copies,” in that they are not readily available(e.g. not mounted to tape or disk). Offline copies can include copies ofdata that the information management system 100 can access without humanintervention (e.g. tapes within an automated tape library, but not yetmounted in a drive), and copies that the information management system100 can access only with at least some human intervention (e.g. tapeslocated at an offsite storage site).

The secondary storage devices 108 can include any suitable type ofstorage device such as, without limitation, one or more tape libraries,disk drives or other magnetic, non-tape storage devices, optical mediastorage devices, solid state storage devices, NAS devices, combinationsof the same, and the like. In some cases, the secondary storage devices108 are provided in a cloud (e.g. a private cloud or one operated by athird-party vendor).

The secondary storage device(s) 108 in some cases comprises a disk arrayor a portion thereof. In some cases, a single storage device (e.g., adisk array) is used for storing both primary data 112 and at least somesecondary copies 116. In one example, a disk array capable of performinghardware snapshots stores primary data 112 and creates and storeshardware snapshots of the primary data 112 as secondary copies 116.

The Use of Intermediary Devices for Creating Secondary Copies

Creating secondary copies can be a challenging task. For instance, therecan be hundreds or thousands of client computing devices 102 continuallygenerating large volumes of primary data 112 to be protected. Also,there can be significant overhead involved in the creation of secondarycopies 116. Moreover, secondary storage devices 108 may be specialpurpose components, and interacting with them can require specializedintelligence.

In some cases, the client computing devices 102 interact directly withthe secondary storage device 108 to create the secondary copies 116.However, in view of the factors described above, this approach cannegatively impact the ability of the client computing devices 102 toserve the applications 110 and produce primary data 112. Further, theclient computing devices 102 may not be optimized for interaction withthe secondary storage devices 108.

Thus, in some embodiments, the information management system 100includes one or more software and/or hardware components which generallyact as intermediaries between the client computing devices 102 and thesecondary storage devices 108. In addition to off-loading certainresponsibilities from the client computing devices 102, theseintermediary components can provide other benefits. For instance, asdiscussed further below with respect to FIG. 1D, distributing some ofthe work involved in creating secondary copies 116 can enhancescalability.

The intermediary components can include one or more secondary storagecomputing devices 106 as shown in FIG. 1A and/or one or more mediaagents, which can be software modules residing on correspondingsecondary storage computing devices 106 (or other appropriate devices).Media agents are discussed below (e.g., with respect to FIGS. 1C-1E).

The secondary storage computing device(s) 106 can comprise anyappropriate type of computing device and can include, withoutlimitation, any of the types of fixed and portable computing devicesdescribed above with respect to the client computing devices 102. Insome cases, the secondary storage computing device(s) 106 includespecialized hardware and/or software componentry for interacting withthe secondary storage devices 108.

To create a secondary copy 116, the client computing device 102communicates the primary data 112 to be copied (or a processed versionthereof) to the designated secondary storage computing device 106, viathe communication pathway 114. The secondary storage computing device106 in turn conveys the received data (or a processed version thereof)to the secondary storage device 108. In some such configurations, thecommunication pathway 114 between the client computing device 102 andthe secondary storage computing device 106 comprises a portion of a LAN,WAN or SAN. In other cases, at least some client computing devices 102communicate directly with the secondary storage devices 108 (e.g., viaFibre Channel or SCSI connections).

Exemplary Primary Data and an Exemplary Secondary Copy

FIG. 1B is a detailed view showing some specific examples of primarydata stored on the primary storage device(s) 104 and secondary copy datastored on the secondary storage device(s) 108, with other components inthe system removed for the purposes of illustration. Stored on theprimary storage device(s) 104 are primary data objects including wordprocessing documents 119A-B, spreadsheets 120, presentation documents122, video files 124, image files 126, email mailboxes 128 (andcorresponding email messages 129A-C), html/xml or other types of markuplanguage files 130, databases 132 and corresponding tables 133A-133C).

Some or all primary data objects are associated with a primary copy ofobject metadata (e.g., “Metal-11”), which may be file system metadataand/or application specific metadata. Stored on the secondary storagedevice(s) 108 are secondary copy objects 134A-C which may include copiesof or otherwise represent corresponding primary data objects andmetadata.

As shown, the secondary copy objects 134A-C can individually representmore than one primary data object. For example, secondary copy dataobject 134A represents three separate primary data objects 133C, 122 and129C (represented as 133C′, 122′ and 129C′, respectively). Moreover, asindicated by the prime mark (′), a secondary copy object may store arepresentation of a primary data object or metadata differently than theoriginal format, e.g., in a compressed, encrypted, deduplicated, orother modified format.

Exemplary Information Management System Architecture

The information management system 100 can incorporate a variety ofdifferent hardware and software components, which can in turn beorganized with respect to one another in many different configurations,depending on the embodiment. There are critical design choices involvedin specifying the functional responsibilities of the components and therole of each component in the information management system 100. Forinstance, as will be discussed, such design choices can impactperformance as well as the adaptability of the information managementsystem 100 to data growth or other changing circumstances.

FIG. 1C shows an information management system 100 designed according tothese considerations and which includes: a central storage orinformation manager 140 configured to perform certain control functions,one or more data agents 142 executing on the client computing device(s)102 configured to process primary data 112, and one or more media agents144 executing on the one or more secondary storage computing devices 106for performing tasks involving the secondary storage devices 108.

Storage Manager

As noted, the number of components in the information management system100 and the amount of data under management can be quite large. Managingthe components and data is therefore a significant task, and a task thatcan grow in an often unpredictable fashion as the quantity of componentsand data scale to meet the needs of the organization.

For these and other reasons, according to certain embodiments,responsibility for controlling the information management system 100, orat least a significant portion of that responsibility, is allocated tothe storage manager 140.

By distributing control functionality in this manner, the storagemanager 140 can be adapted independently according to changingcircumstances. Moreover, a host computing device can be selected to bestsuit the functions of the storage manager 140. These and otheradvantages are described in further detail below with respect to FIG.1D.

The storage manager 140 may be a software module or other application.The storage manager generally initiates, coordinates and/or controlsstorage and other information management operations performed by theinformation management system 100, e.g., to protect and control theprimary data 112 and secondary copies 116 of data and metadata.

As shown by the dashed, arrowed lines, the storage manager 140 maycommunicate with and/or control some or all elements of the informationmanagement system 100, such as the data agents 142 and media agents 144.Thus, in certain embodiments, control information originates from thestorage manager 140, whereas payload data and metadata is generallycommunicated between the data agents 142 and the media agents 144 (orotherwise between the client computing device(s) 102 and the secondarystorage computing device(s) 106), e.g., at the direction of the storagemanager 140. In other embodiments, some information managementoperations are controlled by other components in the informationmanagement system 100 (e.g., the media agent(s) 144 or data agent(s)142), instead of or in combination with the storage manager 140.

According to certain embodiments, the storage manager provides one ormore of the following functions:

-   -   initiating execution of secondary copy operations;    -   managing secondary storage devices 108 and inventory/capacity of        the same;    -   allocating secondary storage devices 108 for secondary storage        operations;    -   monitoring completion of and providing status reporting related        to secondary storage operations;    -   tracking age information relating to secondary copies 116,        secondary storage devices 108, and comparing the age information        against retention guidelines;    -   tracking movement of data within the information management        system 100;    -   tracking logical associations between components in the        information management system 100;    -   protecting metadata associated with the information management        system 100; and    -   implementing operations management functionality.

The storage manager 140 may maintain a database 146 ofmanagement-related data and information management policies 148. Thedatabase 146 may include a management index 150 or other data structurethat stores logical associations between components of the system, userpreferences and/or profiles (e.g., preferences regarding encryption,compression, or deduplication of primary or secondary copy data,preferences regarding the scheduling, type, or other aspects of primaryor secondary copy or other operations, mappings of particularinformation management users or user accounts to certain computingdevices or other components, etc.), management tasks, mediacontainerization, or other useful data. For example, the storage manager140 may use the index 150 to track logical associations between mediaagents 144 and secondary storage devices 108 and/or movement of datafrom primary storage devices 104 to secondary storage devices 108.

Administrators and other employees may be able to manually configure andinitiate certain information management operations on an individualbasis. But while this may be acceptable for some recovery operations orother relatively less frequent tasks, it is often not workable forimplementing on-going organization-wide data protection and management.

Thus, the information management system 100 may utilize informationmanagement policies 148 for specifying and executing informationmanagement operations (e.g., on an automated basis). Generally, aninformation management policy 148 can include a data structure or otherinformation source that specifies a set of parameters (e.g., criteriaand rules) associated with storage or other information managementoperations.

The storage manager database 146 may maintain the information managementpolicies 148 and associated data, although the information managementpolicies 148 can be stored in any appropriate location. For instance, astorage policy may be stored as metadata in a media agent database 152or in a secondary storage device 108 (e.g., as an archive copy) for usein restore operations or other information management operations,depending on the embodiment. Information management policies 148 aredescribed further below.

According to certain embodiments, the storage manager database 146comprises a relational database (e.g., an SQL database) for trackingmetadata, such as metadata associated with secondary copy operations(e.g., what client computing devices 102 and corresponding data wereprotected). This and other metadata may additionally be stored in otherlocations, such as at the secondary storage computing devices 106 or onthe secondary storage devices 108, allowing data recovery without theuse of the storage manager 140.

As shown, the storage manager 140 may include a jobs agent 156, a userinterface 158, and a management agent 154, all of which may beimplemented as interconnected software modules or application programs.

The jobs agent 156 in some embodiments initiates, controls, and/ormonitors the status of some or all storage or other informationmanagement operations previously performed, currently being performed,or scheduled to be performed by the information management system 100.For instance, the jobs agent 156 may access information managementpolicies 148 to determine when and how to initiate and control secondarycopy and other information management operations, as will be discussedfurther.

The user interface 158 may include information processing and displaysoftware, such as a graphical user interface (“GUI”), an applicationprogram interface (“API”), or other interactive interface through whichusers and system processes can retrieve information about the status ofinformation management operations (e.g., storage operations) or issueinstructions to the information management system 100 and itsconstituent components.

The storage manager 140 may also track information that permits it toselect, designate, or otherwise identify content indices, deduplicationdatabases, or similar databases or resources or data sets within itsinformation management cell (or another cell) to be searched in responseto certain queries. Such queries may be entered by the user viainteraction with the user interface 158.

Via the user interface 158, users may optionally issue instructions tothe components in the information management system 100 regardingperformance of storage and recovery operations. For example, a user maymodify a schedule concerning the number of pending secondary copyoperations. As another example, a user may employ the GUI to view thestatus of pending storage operations or to monitor the status of certaincomponents in the information management system 100 (e.g., the amount ofcapacity left in a storage device).

In general, the management agent 154 allows multiple informationmanagement systems 100 to communicate with one another. For example, theinformation management system 100 in some cases may be one informationmanagement subsystem or “cell” of a network of multiple cells adjacentto one another or otherwise logically related in a WAN or LAN. With thisarrangement, the cells may be connected to one another throughrespective management agents 154.

For instance, the management agent 154 can provide the storage manager140 with the ability to communicate with other components within theinformation management system 100 (and/or other cells within a largerinformation management system) via network protocols and applicationprogramming interfaces (“APIs”) including, e.g., HTTP, HTTPS, FTP, REST,virtualization software APIs, cloud service provider APIs, and hostedservice provider APIs. Inter-cell communication and hierarchy isdescribed in greater detail in U.S. Pat. No. 7,035,880, which isincorporated by reference herein.

Data Agents

As discussed, a variety of different types of applications 110 canreside on a given client computing device 102, including operatingsystems, database applications, e-mail applications, and virtualmachines, just to name a few. And, as part of the as part of the processof creating and restoring secondary copies 116, the client computingdevices 102 may be tasked with processing and preparing the primary data112 from these various different applications 110. Moreover, the natureof the processing/preparation can differ across clients and applicationtypes, e.g., due to inherent structural and formatting differencesbetween applications 110.

The one or more data agent(s) 142 are therefore advantageouslyconfigured in some embodiments to assist in the performance ofinformation management operations based on the type of data that isbeing protected, at a client-specific and/or application-specific level.

The data agent 142 may be a software module or component that isgenerally responsible for managing, initiating, or otherwise assistingin the performance of information management operations. For instance,the data agent 142 may take part in performing data storage operationssuch as the copying, archiving, migrating, replicating of primary data112 stored in the primary storage device(s) 104. The data agent 142 mayreceive control information from the storage manager 140, such ascommands to transfer copies of data objects, metadata, and other payloaddata to the media agents 144.

In some embodiments, a data agent 142 may be distributed between theclient computing device 102 and storage manager 140 (and any otherintermediate components) or may be deployed from a remote location orits functions approximated by a remote process that performs some or allof the functions of data agent 142. In addition, a data agent 142 mayperform some functions provided by a media agent 144, e.g., encryptionand deduplication.

As indicated, each data agent 142 may be specialized for a particularapplication 110, and the system can employ multiple data agents 142,each of which may backup, migrate, and recover data associated with adifferent application 110. For instance, different individual dataagents 142 may be designed to handle Microsoft Exchange data, LotusNotes data, Microsoft Windows file system data, Microsoft ActiveDirectory Objects data, SQL Server data, SharePoint data, Oracledatabase data, SAP database data, virtual machines and/or associateddata, and other types of data.

A file system data agent, for example, may handle data files and/orother file system information. If a client computing device 102 has twoor more types of data, one data agent 142 may be used for each data typeto copy, archive, migrate, and restore the client computing device 102data. For example, to backup, migrate, and restore all of the data on aMicrosoft Exchange server, the client computing device 102 may use oneMicrosoft Exchange Mailbox data agent 142 to backup the Exchangemailboxes, one Microsoft Exchange Database data agent 142 to backup theExchange databases, one Microsoft Exchange Public Folder data agent 142to backup the Exchange Public Folders, and one Microsoft Windows FileSystem data agent 142 to backup the file system of the client computingdevice 102. In such embodiments, these data agents 142 may be treated asfour separate data agents 142 by even though they reside on the sameclient computing device 102.

Other embodiments may employ one or more generic data agents 142 thatcan handle and process data from two or more different applications 110,or that can handle and process multiple data types, instead of or inaddition to using specialized data agents 142. For example, one genericdata agent 142 may be used to back up, migrate and restore MicrosoftExchange Mailbox data and Microsoft Exchange Database data while anothergeneric data agent may handle Microsoft Exchange Public Folder data andMicrosoft Windows File System data.

Each data agent 142 may be configured to access data and/or metadatastored in the primary storage device(s) 104 associated with the dataagent 142 and process the data as appropriate. For example, during asecondary copy operation, the data agent 142 may arrange or assemble thedata and metadata into one or more files having a certain format (e.g.,a particular backup or archive format) before transferring the file(s)to a media agent 144 or other component. The file(s) may include a listof files or other metadata. Each data agent 142 can also assist inrestoring data or metadata to primary storage devices 104 from asecondary copy 116. For instance, the data agent 142 may operate inconjunction with the storage manager 140 and one or more of the mediaagents 144 to restore data from secondary storage device(s) 108.

Media Agents

As indicated above with respect to FIG. 1A, off-loading certainresponsibilities from the client computing devices 102 to intermediarycomponents such as the media agent(s) 144 can provide a number ofbenefits including improved client computing device 102 operation,faster secondary copy operation performance, and enhanced scalability.As one specific example which will be discussed below in further detail,the media agent 144 can act as a local cache of copied data and/ormetadata that it has stored to the secondary storage device(s) 108,providing improved restore capabilities.

Generally speaking, a media agent 144 may be implemented as a softwaremodule that manages, coordinates, and facilitates the transmission ofdata, as directed by the storage manager 140, between a client computingdevice 102 and one or more secondary storage devices 108. Whereas thestorage manager 140 controls the operation of the information managementsystem 100, the media agent 144 generally provides a portal to secondarystorage devices 108.

Media agents 144 can comprise logically and/or physically separate nodesin the information management system 100 (e.g., separate from the clientcomputing devices 102, storage manager 140, and/or secondary storagedevices 108). In addition, each media agent 144 may reside on adedicated secondary storage computing device 106 in some cases, while inother embodiments a plurality of media agents 144 reside on the samesecondary storage computing device 106.

A media agent 144 (and corresponding media agent database 152) may beconsidered to be “associated with” a particular secondary storage device108 if that media agent 144 is capable of one or more of: routing and/orstoring data to the particular secondary storage device 108,coordinating the routing and/or storing of data to the particularsecondary storage device 108, retrieving data from the particularsecondary storage device 108, and coordinating the retrieval of datafrom a particular secondary storage device 108.

While media agent(s) 144 are generally associated with one or moresecondary storage devices 108, the media agents 144 in certainembodiments are physically separate from the secondary storage devices108. For instance, the media agents 144 may reside on secondary storagecomputing devices 106 having different housings or packages than thesecondary storage devices 108. In one example, a media agent 144 resideson a first server computer and is in communication with a secondarystorage device(s) 108 residing in a separate, rack-mounted RAID-basedsystem.

In operation, a media agent 144 associated with a particular secondarystorage device 108 may instruct the secondary storage device 108 (e.g.,a tape library) to use a robotic arm or other retrieval means to load oreject a certain storage media, and to subsequently archive, migrate, orretrieve data to or from that media, e.g., for the purpose of restoringthe data to a client computing device 102. The media agent 144 maycommunicate with a secondary storage device 108 via a suitablecommunications link, such as a SCSI or Fiber Channel link.

As will be described in greater detail below with reference to FIG. 2,in some embodiments, a subset of the media agents 114 can be designatedas proxy media agents. In such embodiments, the proxy media agents cancommunicate directly with the secondary storage devices 108 on behalf ofthe other media agents 114. In this manner, the security of thesecondary storage devices 108 can be improved as fewer devices haveaccess to them. In addition, the use of proxy media agents can providegeneric compatibility with certain types of disk arrays, such as EMCClarion, EMC Symmetrix, EMC Celerra, Dell EqualLogic, IBM XIV, NetAppFAS, and HP EVA, and HP 3PAR disk arrays.

As shown, each media agent 144 may maintain an associated media agentdatabase 152. The media agent database 152 may be stored in a disk orother storage device (not shown) that is local to the secondary storagecomputing device 106 on which the media agent 144 resides. In othercases, the media agent database 152 is stored remotely from thesecondary storage computing device 106.

The media agent database 152 can include, among other things, an index153 including data generated during secondary copy operations and otherstorage or information management operations. The index 153 provides amedia agent 144 or other component with a fast and efficient mechanismfor locating secondary copies 116 or other data stored in the secondarystorage devices 108. In one configuration, a storage manager index 150or other data structure may store data associating a client computingdevice 102 with a particular media agent 144 and/or secondary storagedevice 108, as specified in a storage policy. A media agent index 153 orother data structure associated with the particular media agent 144 mayin turn include information about the stored data.

For instance, for each secondary copy 116, the index 153 may includemetadata such as a list of the data objects (e.g., files/subdirectories,database objects, mailbox objects, etc.), a path to the secondary copy116 on the corresponding secondary storage device 108, locationinformation indicating where the data objects are stored in thesecondary storage device 108, when the data objects were created ormodified, etc. Thus, the index 153 includes metadata associated with thesecondary copies 116 that is readily available for use in storageoperations and other activities without having to be first retrievedfrom the secondary storage device 108. In yet further embodiments, someor all of the data in the index 153 may instead or additionally bestored along with the data in a secondary storage device 108, e.g., witha copy of the index 153.

Because the index 153 maintained in the database 152 may operate as acache, it can also be referred to as an index cache. In such cases,information stored in the index cache 153 typically comprises data thatreflects certain particulars about storage operations that have occurredrelatively recently. After some triggering event, such as after acertain period of time elapses, or the index cache 153 reaches aparticular size, the index cache 153 may be copied or migrated to asecondary storage device(s) 108. This information may need to beretrieved and uploaded back into the index cache 153 or otherwiserestored to a media agent 144 to facilitate retrieval of data from thesecondary storage device(s) 108. In some embodiments, the cachedinformation may include format or containerization information relatedto archives or other files stored on the storage device(s) 108. In thismanner, the index cache 153 allows for accelerated restores.

In some alternative embodiments the media agent 144 generally acts as acoordinator or facilitator of storage operations between clientcomputing devices 102 and corresponding secondary storage devices 108,but does not actually write the data to the secondary storage device108. For instance, the storage manager 140 (or the media agent 144) mayinstruct a client computing device 102 and secondary storage device 108to communicate with one another directly. In such a case the clientcomputing device 102 transmits the data directly to the secondarystorage device 108 according to the received instructions, and viceversa. In some such cases, the media agent 144 may still receive,process, and/or maintain metadata related to the storage operations.Moreover, in these embodiments, the payload data can flow through themedia agent 144 for the purposes of populating the index cache 153maintained in the media agent database 152, but not for writing to thesecondary storage device 108.

The media agent 144 and/or other components such as the storage manager140 may in some cases incorporate additional functionality, such as dataclassification, content indexing, deduplication, encryption,compression, and the like. Further details regarding these and otherfunctions are described below.

Distributed, Scalable Architecture

As described, certain functions of the information management system 100can be distributed amongst various physical and/or logical components inthe system. For instance, one or more of the storage manager 140, dataagents 142, and media agents 144 may reside on computing devices thatare physically separate from one another. This architecture can providea number of benefits.

For instance, hardware and software design choices for each distributedcomponent can be targeted to suit its particular function. The secondarycomputing devices 106 on which the media agents 144 reside can betailored for interaction with associated secondary storage devices 108and provide fast index cache operation, among other specific tasks.Similarly, the client computing device(s) 102 can be selected toeffectively service the applications 110 residing thereon, in order toefficiently produce and store primary data 112.

Moreover, in some cases, one or more of the individual components in theinformation management system 100 can be distributed to multiple,separate computing devices. As one example, for large file systems wherethe amount of data stored in the storage management database 146 isrelatively large, the management database 146 may be migrated to orotherwise reside on a specialized database server (e.g., an SQL server)separate from a server that implements the other functions of thestorage manager 140. This configuration can provide added protectionbecause the database 146 can be protected with standard databaseutilities (e.g., SQL log shipping or database replication) independentfrom other functions of the storage manager 140. The database 146 can beefficiently replicated to a remote site for use in the event of adisaster or other data loss incident at the primary site. Or thedatabase 146 can be replicated to another computing device within thesame site, such as to a higher performance machine in the event that astorage manager host device can no longer service the needs of a growinginformation management system 100.

The distributed architecture also provides both scalability andefficient component utilization. FIG. 1D shows an embodiment of theinformation management system 100 including a plurality of clientcomputing devices 102 and associated data agents 142 as well as aplurality of secondary storage computing devices 106 and associatedmedia agents 144.

Additional components can be added or subtracted based on the evolvingneeds of the information management system 100. For instance, dependingon where bottlenecks are identified, administrators can add additionalclient computing devices 102, secondary storage devices 106 (andcorresponding media agents 144), and/or secondary storage devices 108.

Moreover, each client computing device 102 in some embodiments cancommunicate with any of the media agents 144, e.g., as directed by thestorage manager 140. And each media agent 144 may be able to communicatewith any of the secondary storage devices 108, e.g., as directed by thestorage manager 140. Thus, operations can be routed to the secondarystorage devices 108 in a dynamic and highly flexible manner. Furtherexamples of scalable systems capable of dynamic storage operations areprovided in U.S. Pat. No. 7,246,207, which is incorporated by referenceherein.

In alternative configurations, certain components are not distributedand may instead reside and execute on the same computing device. Forexample, in some embodiments one or more data agents 142 and the storagemanager 140 reside on the same client computing device 102. In anotherembodiment, one or more data agents 142 and one or more media agents 144reside on a single computing device.

Exemplary Types of Information Management Operations

In order to protect and leverage stored data, the information managementsystem 100 can be configured to perform a variety of informationmanagement operations. As will be described, these operations cangenerally include secondary copy and other data movement operations,processing and data manipulation operations, and management operations.

Data Movement Operations

Data movement operations according to certain embodiments are generallyoperations that involve the copying or migration of data (e.g., payloaddata) between different locations in the information management system100. For example, data movement operations can include operations inwhich stored data is copied, migrated, or otherwise transferred fromprimary storage device(s) 104 to secondary storage device(s) 108, fromsecondary storage device(s) 108 to different secondary storage device(s)108, or from primary storage device(s) 104 to different primary storagedevice(s) 104.

Data movement operations can include by way of example, backupoperations, archive operations, information lifecycle managementoperations such as hierarchical storage management operations,replication operations (e.g., continuous data replication operations),snapshot operations, deduplication operations, single-instancingoperations, auxiliary copy operations, and the like. As will bediscussed, some of these operations involve the copying, migration orother movement of data, without actually creating multiple, distinctcopies. Nonetheless, some or all of these operations are referred to as“copy” operations for simplicity.

Backup Operations

A backup operation creates a copy of primary data 112 at a particularpoint in time. Each subsequent backup copy may be maintainedindependently of the first. Further, a backup copy in some embodimentsis stored in a backup format. This can be in contrast to the version inprimary data 112 from which the backup copy is derived, and which mayinstead be stored in a native format of the source application(s) 110.In various cases, backup copies can be stored in a format in which thedata is compressed, encrypted, deduplicated, and/or otherwise modifiedfrom the original application format. For example, a backup copy may bestored in a backup format that facilitates compression and/or efficientlong-term storage.

Backup copies can have relatively long retention periods as compared toprimary data 112, and may be stored on media with slower retrieval timesthan primary data 112 and certain other types of secondary copies 116.On the other hand, backups may have relatively shorter retention periodsthan some other types of secondary copies 116, such as archive copies(described below). Backups may sometimes be stored at on offsitelocation.

Backup operations can include full, synthetic or incremental backups. Afull backup in some embodiments is generally a complete image of thedata to be protected. However, because full backup copies can consume arelatively large amount of storage, it can be useful to use a fullbackup copy as a baseline and only store changes relative to the fullbackup copy for subsequent backup copies.

For instance, a differential backup operation (or cumulative incrementalbackup operation) tracks and stores changes that have occurred since thelast full backup. Differential backups can grow quickly in size, but canprovide relatively efficient restore times because a restore can becompleted in some cases using only the full backup copy and the latestdifferential copy.

An incremental backup operation generally tracks and stores changessince the most recent backup copy of any type, which can greatly reducestorage utilization. In some cases, however, restore times can berelatively long in comparison to full or differential backups becausecompleting a restore operation may involve accessing a full backup inaddition to multiple incremental backups.

Any of the above types of backup operations can be at the file-level,e.g., where the information management system 100 generally trackschanges to files at the file-level, and includes copies of files in thebackup copy. In other cases, block-level backups are employed, wherefiles are broken into constituent blocks, and changes are tracked at theblock-level. Upon restore, the information management system 100reassembles the blocks into files in a transparent fashion.

Far less data may actually be transferred and copied to the secondarystorage devices 108 during a block-level copy than during a file-levelcopy, resulting in faster execution times. However, when restoring ablock-level copy, the process of locating constituent blocks cansometimes result in longer restore times as compared to file-levelbackups. Similar to backup operations, the other types of secondary copyoperations described herein can also be implemented at either thefile-level or the block-level.

Archive Operations

Because backup operations generally involve maintaining a version of thecopied data in primary data 112 and also maintaining backup copies insecondary storage device(s) 108, they can consume significant storagecapacity. To help reduce storage consumption, an archive operationaccording to certain embodiments creates a secondary copy 116 by bothcopying and removing source data. Or, seen another way, archiveoperations can involve moving some or all of the source data to thearchive destination. Thus, data satisfying criteria for removal (e.g.,data of a threshold age or size) from the source copy may be removedfrom source storage. Archive copies are sometimes stored in an archiveformat or other non-native application format. The source data may beprimary data 112 or a secondary copy 116, depending on the situation. Aswith backup copies, archive copies can be stored in a format in whichthe data is compressed, encrypted, deduplicated, and/or otherwisemodified from the original application format.

In addition, archive copies may be retained for relatively long periodsof time (e.g., years) and, in some cases, are never deleted. Archivecopies are generally retained for longer periods of time than backupcopies, for example. In certain embodiments, archive copies may be madeand kept for extended periods in order to meet compliance regulations.

Moreover, when primary data 112 is archived, in some cases the archivedprimary data 112 or a portion thereof is deleted when creating thearchive copy. Thus, archiving can serve the purpose of freeing up spacein the primary storage device(s) 104. Similarly, when a secondary copy116 is archived, the secondary copy 116 may be deleted, and an archivecopy can therefore serve the purpose of freeing up space in secondarystorage device(s) 108. In contrast, source copies often remain intactwhen creating backup copies.

Snapshot Operations

Snapshot operations can provide a relatively lightweight, efficientmechanism for protecting data. From an end-user viewpoint, a snapshotmay be thought of as an “instant” image of the primary data 112 at agiven point in time. In one embodiment, a snapshot may generally capturethe directory structure of an object in primary data 112 such as a fileor volume or other data set at a particular moment in time and may alsopreserve file attributes and contents. A snapshot in some cases iscreated relatively quickly, e.g., substantially instantly, using aminimum amount of file space, but may still function as a conventionalfile system backup.

A snapshot copy in many cases can be made quickly and withoutsignificantly impacting primary computing resources because largeamounts of data need not be copied or moved. In some embodiments, asnapshot may exist as a virtual file system, parallel to the actual filesystem. Users in some cases gain read-only access to the record of filesand directories of the snapshot. By electing to restore primary data 112from a snapshot taken at a given point in time, users may also returnthe current file system to the state of the file system that existedwhen the snapshot was taken.

Some types of snapshots do not actually create another physical copy ofall the data as it existed at the particular point in time, but maysimply create pointers that are able to map files and directories tospecific memory locations (e.g., disk blocks) where the data resides, asit existed at the particular point in time. For example, a snapshot copymay include a set of pointers derived from the file system or anapplication. Each pointer points to a respective stored data block, socollectively, the set of pointers reflect the storage location and stateof the data object (e.g., file(s) or volume(s) or data set(s)) at aparticular point in time when the snapshot copy was created.

In some embodiments, once a snapshot has been taken, subsequent changesto the file system typically do not overwrite the blocks in use at thetime of the snapshot. Therefore, the initial snapshot may use only asmall amount of disk space needed to record a mapping or other datastructure representing or otherwise tracking the blocks that correspondto the current state of the file system. Additional disk space isusually required only when files and directories are actually modifiedlater. Furthermore, when files are modified, typically only the pointerswhich map to blocks are copied, not the blocks themselves. In someembodiments, for example in the case of “copy-on-write” snapshots, whena block changes in primary storage, the block is copied to secondarystorage or cached in primary storage before the block is overwritten inprimary storage. The snapshot mapping of file system data is alsoupdated to reflect the changed block(s) at that particular point intime. In some other cases, a snapshot includes a full physical copy ofall or substantially all of the data represented by the snapshot.Further examples of snapshot operations are provided in U.S. Pat. No.7,529,782, which is incorporated by reference herein.

Replication Operations

Another type of secondary copy operation is a replication operation.Some types of secondary copies 116 are used to periodically captureimages of primary data 112 at particular points in time (e.g., backups,archives, and snapshots). However, it can also be useful for recoverypurposes to protect primary data 112 in a more continuous fashion, byreplicating the primary data 112 substantially as changes occur. In somecases a replication copy can be a mirror copy, for instance, wherechanges made to primary data 112 are mirrored to another location (e.g.,to secondary storage device(s) 108). By copying each write operation tothe replication copy, two storage systems are kept synchronized orsubstantially synchronized so that they are virtually identical atapproximately the same time. Where entire disk volumes are mirrored,however, mirroring can require significant amount of storage space andutilizes a large amount of processing resources.

According to some embodiments storage operations are performed onreplicated data that represents a recoverable state, or “known goodstate” of a particular application running on the source system. Forinstance, in certain embodiments, known good replication copies may beviewed as copies of primary data 112. This feature allows the system todirectly access, copy, restore, backup or otherwise manipulate thereplication copies as if the data was the “live”, primary data 112. Thiscan reduce access time, storage utilization, and impact on sourceapplications 110, among other benefits.

Based on known good state information, the information management system100 can replicate sections of application data that represent arecoverable state rather than rote copying of blocks of data. Examplesof compatible replication operations (e.g., continuous data replication)are provided in U.S. Pat. No. 7,617,262, which is incorporated byreference herein.

Deduplication/Single-Instancing Operations

Another type of data movement operation is deduplication, which isuseful to reduce the amount of data within the system. For instance,some or all of the above-described secondary storage operations caninvolve deduplication in some fashion. New data is read, broken downinto blocks (e.g., sub-file level blocks) of a selected granularity,compared with blocks that are already stored, and only the new blocksare stored. Blocks that already exist are represented as pointers to thealready stored data.

In order to stream-line the comparison process, the informationmanagement system 100 may calculate and/or store signatures (e.g.,hashes) corresponding to the individual data blocks and compare thehashes instead of comparing entire data blocks. In some cases, only asingle instance of each element is stored, and deduplication operationsmay therefore be referred to interchangeably as “single-instancing”operations. Depending on the implementation, however, deduplication orsingle-instancing operations can store more than one instance of certaindata blocks, but nonetheless significantly reduce data redundancy.Moreover, single-instancing in some cases is distinguished fromdeduplication as a process of analyzing and reducing data at the filelevel, rather than the sub-file level.

Depending on the embodiment, deduplication blocks can be of fixed orvariable length. Using variable length blocks can provide enhanceddeduplication by responding to changes in the data stream, but caninvolve complex processing. In some cases, the information managementsystem 100 utilizes a technique for dynamically aligning deduplicationblocks (e.g., fixed-length blocks) based on changing content in the datastream, as described in U.S. Pat. Pub. No. 2012/0084269, which isincorporated by reference herein.

The information management system 100 can perform deduplication in avariety of manners at a variety of locations in the informationmanagement system 100. For instance, in some embodiments, theinformation management system 100 implements “target-side” deduplicationby deduplicating data (e.g., secondary copies 116) stored in thesecondary storage devices 108. In some such cases, the media agents 144are generally configured to manage the deduplication process. Forinstance, one or more of the media agents 144 maintain a correspondingdeduplication database that stores deduplication information (e.g.,datablock signatures). Examples of such a configuration are provided inU.S. Pat. Pub. No. 2012/0150826, which is incorporated by referenceherein. Deduplication can also be performed on the “source-side” (or“client-side”), e.g., to reduce the amount of traffic between the mediaagents 144 and the client computing device(s) 102 and/or reduceredundant data stored in the primary storage devices 104. Examples ofsuch deduplication techniques are provided in U.S. Pat. Pub. No.2012/0150818, which is incorporated by reference herein.

Information Lifecycle Management and Hierarchical Storage ManagementOperations

In some embodiments, files and other data over their lifetime move frommore expensive, quick access storage to less expensive, slower accessstorage. Operations associated with moving data through various tiers ofstorage are sometimes referred to as information lifecycle management(ILM) operations.

One type of ILM operation is a hierarchical storage management (HSM)operation. A HSM operation is generally an operation for automaticallymoving data between classes of storage devices, such as betweenhigh-cost and low-cost storage devices. For instance, an HSM operationmay involve movement of data from primary storage devices 104 tosecondary storage devices 108, or between tiers of secondary storagedevices 108. With each tier, the storage devices may be progressivelyrelatively cheaper, have relatively slower access/restore times, etc.For example, movement of data between tiers may occur as data becomesless important over time.

In some embodiments, an HSM operation is similar to an archive operationin that creating an HSM copy may (though not always) involve deletingsome of the source data. For example, an HSM copy may include data fromprimary data 112 or a secondary copy 116 that is larger than a givensize threshold or older than a given age threshold and that is stored ina backup format.

Often, and unlike some types of archive copies, HSM data that is removedor aged from the source copy is replaced by a logical reference pointeror stub. The reference pointer or stub can be stored in the primarystorage device 104 to replace the deleted data in primary data 112 (orother source copy) and to point to or otherwise indicate the newlocation in a secondary storage device 108.

According to one example, files are generally moved between higher andlower cost storage depending on how often the files are accessed. When auser requests access to the HSM data that has been removed or migrated,the information management system 100 uses the stub to locate the dataand often make recovery of the data appear transparent, even though theHSM data may be stored at a location different from the remaining sourcedata. The stub may also include some metadata associated with thecorresponding data, so that a file system and/or application can providesome information about the data object and/or a limited-functionalityversion (e.g., a preview) of the data object.

An HSM copy may be stored in a format other than the native applicationformat (e.g., where the data is compressed, encrypted, deduplicated,and/or otherwise modified from the original application format). In somecases, copies which involve the removal of data from source storage andthe maintenance of stub or other logical reference information on sourcestorage may be referred to generally as “on-line archive copies”. On theother hand, copies which involve the removal of data from source storagewithout the maintenance of stub or other logical reference informationon source storage may be referred to as “off-line archive copies”.

Auxiliary Copy and Disaster Recovery Operations

An auxiliary copy is generally a copy operation in which a copy iscreated of an existing secondary copy 116. For instance, an initial or“primary” secondary copy 116 may be generated using or otherwise bederived from primary data 112, whereas an auxiliary copy is generatedfrom the initial secondary copy 116. Auxiliary copies can be used tocreate additional standby copies of data and may reside on differentsecondary storage devices 108 than initial secondary copies 116. Thus,auxiliary copies can be used for recovery purposes if initial secondarycopies 116 become unavailable. Exemplary compatible auxiliary copytechniques are described in further detail in U.S. Pat. No. 8,230,195,which is incorporated by reference herein.

The information management system 100 may also perform disaster recoveryoperations that make or retain disaster recovery copies, often assecondary, high-availability disk copies. The information managementsystem 100 may create secondary disk copies and store the copies atdisaster recovery locations using auxiliary copy or replicationoperations, such as continuous data replication technologies. Dependingon the particular data protection goals, disaster recovery locations canbe remote from the client computing devices 102 and primary storagedevices 104, remote from some or all of the secondary storage devices108, or both.

Data Processing and Manipulation Operations

As indicated, the information management system 100 can also beconfigured to implement certain data manipulation operations, whichaccording to certain embodiments are generally operations involving theprocessing or modification of stored data. Some data manipulationoperations include content indexing operations and classificationoperations can be useful in leveraging the data under management toprovide enhanced search and other features. Other data manipulationoperations such as compression and encryption can provide data reductionand security benefits, respectively.

Data manipulation operations can be different than data movementoperations in that they do not necessarily involve the copying,migration or other transfer of data (e.g., primary data 112 or secondarycopies 116) between different locations in the system. For instance,data manipulation operations may involve processing (e.g., offlineprocessing) or modification of already stored primary data 112 and/orsecondary copies 116. However, in some embodiments data manipulationoperations are performed in conjunction with data movement operations.As one example, the information management system 100 may encrypt datawhile performing an archive operation.

Content Indexing

In some embodiments, the information management system 100 “contentindexes” data stored within the primary data 112 and/or secondary copies116, providing enhanced search capabilities for data discovery and otherpurposes. The content indexing can be used to identify files or otherdata objects having pre-defined content (e.g., user-defined keywords orphrases), metadata (e.g., email metadata such as “to”, “from”, “cc”,“bcc”, attachment name, received time, etc.).

The information management system 100 generally organizes and cataloguesthe results in a content index, which may be stored within the mediaagent database 152, for example. The content index can also include thestorage locations of (or pointer references to) the indexed data in theprimary data 112 or secondary copies 116, as appropriate. The resultsmay also be stored, in the form of a content index database orotherwise, elsewhere in the information management system 100 (e.g., inthe primary storage devices 104, or in the secondary storage device108). Such index data provides the storage manager 140 or anothercomponent with an efficient mechanism for locating primary data 112and/or secondary copies 116 of data objects that match particularcriteria.

For instance, search criteria can be specified by a user through userinterface 158 of the storage manager 140. In some cases, the informationmanagement system 100 analyzes data and/or metadata in secondary copies116 to create an “off-line” content index, without significantlyimpacting the performance of the client computing devices 102. Dependingon the embodiment, the system can also implement “on-line” contentindexing, e.g., of primary data 112. Examples of compatible contentindexing techniques are provided in U.S. Pat. No. 8,170,995, which isincorporated by reference herein.

Classification Operations—Metabase

In order to help leverage the data stored in the information managementsystem 100, one or more components can be configured to scan data and/orassociated metadata for classification purposes to populate a metabaseof information. Such scanned, classified data and/or metadata may beincluded in a separate database and/or on a separate storage device fromprimary data 112 (and/or secondary copies 116), such that metabaserelated operations do not significantly impact performance on othercomponents in the information management system 100.

In other cases, the metabase(s) may be stored along with primary data112 and/or secondary copies 116. Files or other data objects can beassociated with user-specified identifiers (e.g., tag entries) in themedia agent 144 (or other indices) to facilitate searches of stored dataobjects. Among a number of other benefits, the metabase can also allowefficient, automatic identification of files or other data objects toassociate with secondary copy or other information management operations(e.g., in lieu of scanning an entire file system). Examples ofcompatible metabases and data classification operations are provided inU.S. Pat. Nos. 8,229,954 and 7,747,579, which are incorporated byreference herein.

Encryption Operations

The information management system 100 in some cases is configured toprocess data (e.g., files or other data objects, secondary copies 116,etc.), according to an appropriate encryption algorithm (e.g., Blowfish,Advanced Encryption Standard [AES], Triple Data Encryption Standard[3-DES], etc.) to limit access and provide data security in theinformation management system 100.

The information management system 100 in some cases encrypts the data atthe client level, such that the client computing devices 102 (e.g., thedata agents 142) encrypt the data prior to forwarding the data to othercomponents, e.g., before sending the data media agents 144 during asecondary copy operation. In such cases, the client computing device 102may maintain or have access to an encryption key or passphrase fordecrypting the data upon restore. Encryption can also occur whencreating copies of secondary copies, e.g., when creating auxiliarycopies. In yet further embodiments, the secondary storage devices 108can implement built-in, high performance hardware encryption.

Management Operations

Certain embodiments leverage the integrated, ubiquitous nature of theinformation management system 100 to provide useful system-widemanagement functions. As two non-limiting examples, the informationmanagement system 100 can be configured to implement operationsmanagement and e-discovery functions.

Operations management can generally include monitoring and managing thehealth and performance of information management system 100 by, withoutlimitation, performing error tracking, generating granularstorage/performance metrics (e.g., job success/failure information,deduplication efficiency, etc.), generating storage modeling and costinginformation, and the like.

Such information can be provided to users via the user interface 158 ina single, integrated view. For instance, the integrated user interface158 can include an option to show a “virtual view” of the system thatgraphically depicts the various components in the system usingappropriate icons. The operations management functionality canfacilitate planning and decision-making. For example, in someembodiments, a user may view the status of some or all jobs as well asthe status of each component of the information management system 100.Users may then plan and make decisions based on this data. For instance,a user may view high-level information regarding storage operations forthe information management system 100, such as job status, componentstatus, resource status (e.g., network pathways, etc.), and otherinformation. The user may also drill down or use other means to obtainmore detailed information regarding a particular component, job, or thelike.

In some cases the information management system 100 alerts a user suchas a system administrator when a particular resource is unavailable orcongested. For example, a particular primary storage device 104 orsecondary storage device 108 might be full or require additionalcapacity. Or a component may be unavailable due to hardware failure,software problems, or other reasons. In response, the informationmanagement system 100 may suggest solutions to such problems when theyoccur (or provide a warning prior to occurrence). For example, thestorage manager 140 may alert the user that a secondary storage device108 is full or otherwise congested. The storage manager 140 may thensuggest, based on job and data storage information contained in itsdatabase 146, an alternate secondary storage device 108.

Other types of corrective actions may include suggesting an alternatedata path to a particular primary or secondary storage device 104, 108,or dividing data to be stored among various available primary orsecondary storage devices 104, 108 as a load balancing measure or tootherwise optimize storage or retrieval time. Such suggestions orcorrective actions may be performed automatically, if desired. Furtherexamples of some compatible operations management techniques and ofinterfaces providing an integrated view of an information managementsystem are provided in U.S. Pat. No. 7,343,453, which is incorporated byreference herein. In some embodiments, the storage manager 140implements the operations management functions described herein.

The information management system 100 can also be configured to performsystem-wide e-discovery operations in some embodiments. In general,e-discovery operations provide a unified collection and searchcapability for data in the system, such as data stored in the secondarystorage devices 108 (e.g., backups, archives, or other secondary copies116). For example, the information management system 100 may constructand maintain a virtual repository for data stored in the informationmanagement system 100 that is integrated across source applications 110,different storage device types, etc. According to some embodiments,e-discovery utilizes other techniques described herein, such as dataclassification and/or content indexing.

Information Management Policies

As indicated previously, an information management policy 148 caninclude a data structure or other information source that specifies aset of parameters (e.g., criteria and rules) associated with secondarycopy or other information management operations.

One type of information management policy 148 is a storage policy.According to certain embodiments, a storage policy generally comprises alogical container that defines (or includes information sufficient todetermine) one or more of the following items: (1) what data will beassociated with the storage policy; (2) a destination to which the datawill be stored; (3) datapath information specifying how the data will becommunicated to the destination; (4) the type of storage operation to beperformed; and (5) retention information specifying how long the datawill be retained at the destination.

Data associated with a storage policy can be logically organized intogroups, which can be referred to as “sub-clients”. A sub-client mayrepresent static or dynamic associations of portions of a data volume.Sub-clients may represent mutually exclusive portions. Thus, in certainembodiments, a portion of data may be given a label and the associationis stored as a static entity in an index, database or other storagelocation.

Sub-clients may also be used as an effective administrative scheme oforganizing data according to data type, department within theenterprise, storage preferences, or the like. Depending on theconfiguration, sub-clients can correspond to files, folders, virtualmachines, databases, etc. In one exemplary scenario, an administratormay find it preferable to separate e-mail data from financial data usingtwo different sub-clients.

A storage policy can define where data is stored by specifying a targetor destination storage device (or group of storage devices). Forinstance, where the secondary storage device 108 includes a group ofdisk libraries, the storage policy may specify a particular disk libraryfor storing the sub-clients associated with the policy. As anotherexample, where the secondary storage devices 108 include one or moretape libraries, the storage policy may specify a particular tape libraryfor storing the sub-clients associated with the storage policy, and mayalso specify a drive pool and a tape pool defining a group of tapedrives and a group of tapes, respectively, for use in storing thesub-client data.

Datapath information can also be included in the storage policy. Forinstance, the storage policy may specify network pathways and componentsto utilize when moving the data to the destination storage device(s). Insome embodiments, the storage policy specifies one or more media agents144 for conveying data (e.g., one or more sub-clients) associated withthe storage policy between the source (e.g., one or more host clientcomputing devices 102) and destination (e.g., a particular targetsecondary storage device 108).

A storage policy can also specify the type(s) of operations associatedwith the storage policy, such as a backup, archive, snapshot, auxiliarycopy, or the like. Retention information can specify how long the datawill be kept, depending on organizational needs (e.g., a number of days,months, years, etc.)

The information management policies 148 may also include one or morescheduling policies specifying when and how often to perform operations.Scheduling information may specify with what frequency (e.g., hourly,weekly, daily, event-based, etc.) or under what triggering conditionssecondary copy or other information management operations will takeplace. Scheduling policies in some cases are associated with particularcomponents, such as particular sub-clients, client computing device 102,and the like. In one configuration, a separate scheduling policy ismaintained for particular sub-clients on a client computing device 102.The scheduling policy specifies that those sub-clients are to be movedto secondary storage devices 108 every hour according to storagepolicies associated with the respective sub-clients.

When adding a new client computing device 102, administrators canmanually configure information management policies 148 and/or othersettings, e.g., via the user interface 158. However, this can be aninvolved process resulting in delays, and it may be desirable to begindata protecting operations quickly.

Thus, in some embodiments, the information management system 100automatically applies a default configuration to client computing device102. As one example, when a data agent(s) 142 is installed on a clientcomputing devices 102, the installation script may register the clientcomputing device 102 with the storage manager 140, which in turn appliesthe default configuration to the new client computing device 102. Inthis manner, data protection operations can begin substantiallyimmediately. The default configuration can include a default storagepolicy, for example, and can specify any appropriate informationsufficient to begin data protection operations. This can include a typeof data protection operation, scheduling information, a target secondarystorage device 108, data path information (e.g., a particular mediaagent 144), and the like.

Other types of information management policies 148 are possible. Forinstance, the information management policies 148 can also include oneor more audit or security policies. An audit policy is a set ofpreferences, rules and/or criteria that protect sensitive data in theinformation management system 100. For example, an audit policy maydefine “sensitive objects” as files or objects that contain particularkeywords (e.g. “confidential,” or “privileged”) and/or are associatedwith particular keywords (e.g., in metadata) or particular flags (e.g.,in metadata identifying a document or email as personal, confidential,etc.).

An audit policy may further specify rules for handling sensitiveobjects. As an example, an audit policy may require that a reviewerapprove the transfer of any sensitive objects to a cloud storage site,and that if approval is denied for a particular sensitive object, thesensitive object should be transferred to a local storage device 104instead. To facilitate this approval, the audit policy may furtherspecify how a secondary storage computing device 106 or other systemcomponent should notify a reviewer that a sensitive object is slated fortransfer.

In some implementations, the information management policies 148 mayinclude one or more provisioning policies. A provisioning policy caninclude a set of preferences, priorities, rules, and/or criteria thatspecify how clients 102 (or groups thereof) may utilize systemresources, such as available storage on cloud storage and/or networkbandwidth. A provisioning policy specifies, for example, data quotas forparticular client computing devices 102 (e.g. a number of gigabytes thatcan be stored monthly, quarterly or annually). The storage manager 140or other components may enforce the provisioning policy. For instance,the media agents 144 may enforce the policy when transferring data tosecondary storage devices 108. If a client computing device 102 exceedsa quota, a budget for the client computing device 102 (or associateddepartment) is adjusted accordingly or an alert may trigger.

While the above types of information management policies 148 have beendescribed as separate policies, one or more of these can be generallycombined into a single information management policy 148. For instance,a storage policy may also include or otherwise be associated with one ormore scheduling, audit, or provisioning policies. Moreover, whilestorage policies are typically associated with moving and storing data,other policies may be associated with other types of informationmanagement operations. The following is a non-exhaustive list of itemsthe information management policies 148 may specify:

-   -   schedules or other timing information, e.g., specifying when        and/or how often to perform information management operations;    -   the type of secondary copy 116 and/or secondary copy format        (e.g., snapshot, backup, archive, HSM, etc.);    -   a location or a class or quality of storage for storing        secondary copies 116 (e.g., one or more particular secondary        storage devices 108);    -   preferences regarding whether and how to encrypt, compress,        deduplicate, or otherwise modify or transform secondary copies        116;    -   which system components and/or network pathways (e.g., preferred        media agents 144) should be used to perform secondary storage        operations;    -   resource allocation between different computing devices or other        system components used in performing information management        operations (e.g., bandwidth allocation, available storage        capacity, etc.);    -   whether and how to synchronize or otherwise distribute files or        other data objects across multiple computing devices or hosted        services; and    -   retention information specifying the length of time primary data        112 and/or secondary copies 116 should be retained, e.g., in a        particular class or tier of storage devices, or within the        information management system 100.

Policies can additionally specify or depend on a variety of historicalor current criteria that may be used to determine which rules to applyto a particular data object, system component, or information managementoperation, such as:

-   -   frequency with which primary data 112 or a secondary copy 116 of        a data object or metadata has been or is predicted to be used,        accessed, or modified;    -   time-related factors (e.g., aging information such as time since        the creation or modification of a data object);    -   deduplication information (e.g., hashes, data blocks,        deduplication block size, deduplication efficiency or other        metrics);    -   an estimated or historic usage or cost associated with different        components (e.g., with secondary storage devices 108);    -   the identity of users, applications 110, client computing        devices 102 and/or other computing devices that created,        accessed, modified, or otherwise utilized primary data 112 or        secondary copies 116;    -   a relative sensitivity (e.g., confidentiality) of a data object,        e.g., as determined by its content and/or metadata;    -   the current or historical storage capacity of various storage        devices;    -   the current or historical network capacity of network pathways        connecting various components within the storage operation cell;    -   access control lists or other security information; and    -   the content of a particular data object (e.g., its textual        content) or of metadata associated with the data object.        Exemplary Storage Policy and Secondary Storage Operations

FIG. 1E shows a data flow data diagram depicting performance of storageoperations by an embodiment of an information management system 100,according to an exemplary data storage policy 148A. The informationmanagement system 100 includes a storage manger 140, a client computingdevice 102 having a file system data agent 142A and an email data agent142B residing thereon, a primary storage device 104, two media agents144A, 144B, and two secondary storage devices 108A, 108B: a disk library108A and a tape library 108B. As shown, the primary storage device 104includes primary data 112A, 112B associated with a file systemsub-client and an email sub-client, respectively.

As indicated by the dashed box, the second media agent 144B and the tapelibrary 108B are “off-site”, and may therefore be remotely located fromthe other components in the information management system 100 (e.g., ina different city, office building, etc.). In this manner, informationstored on the tape library 108B may provide protection in the event of adisaster or other failure.

The file system sub-client and its associated primary data 112A incertain embodiments generally comprise information generated by the filesystem and/or operating system of the client computing device 102, andcan include, for example, file system data (e.g., regular files, filetables, mount points, etc.), operating system data (e.g., registries,event logs, etc.), and the like. The e-mail sub-client, on the otherhand, and its associated primary data 112B, include data generated by ane-mail client application operating on the client computing device 102,and can include mailbox information, folder information, emails,attachments, associated database information, and the like. As describedabove, the sub-clients can be logical containers, and the data includedin the corresponding primary data 112A, 112B may or may not be storedcontiguously.

The exemplary storage policy 148A includes a backup copy rule set 160, adisaster recovery copy rule set 162, and a compliance copy rule set 164.The backup copy rule set 160 specifies that it is associated with a filesystem sub-client 166 and an email sub-client 168. Each of thesesub-clients 166, 168 are associated with the particular client computingdevice 102. The backup copy rule set 160 further specifies that thebackup operation will be written to the disk library 108A, anddesignates a particular media agent 144A to convey the data to the disklibrary 108A. Finally, the backup copy rule set 160 specifies thatbackup copies created according to the rule set 160 are scheduled to begenerated on an hourly basis and to be retained for 30 days. In someother embodiments, scheduling information is not included in the storagepolicy 148A, and is instead specified by a separate scheduling policy.

The disaster recovery copy rule set 162 is associated with the same twosub-clients 166, 168. However, the disaster recovery copy rule set 162is associated with the tape library 108B, unlike the backup copy ruleset 160. Moreover, the disaster recovery copy rule set 162 specifiesthat a different media agent 144B than the media agent 144A associatedwith the backup copy rule set 160 will be used to convey the data to thetape library 108B. As indicated, disaster recovery copies createdaccording to the rule set 162 will be retained for 60 days, and will begenerated on a daily basis. Disaster recovery copies generated accordingto the disaster recovery copy rule set 162 can provide protection in theevent of a disaster or other data-loss event that would affect thebackup copy 116A maintained on the disk library 108A.

The compliance copy rule set 164 is only associated with the emailsub-client 166, and not the file system sub-client 168. Compliancecopies generated according to the compliance copy rule set 164 willtherefore not include primary data 112A from the file system sub-client166. For instance, the organization may be under an obligation to storemaintain copies of email data for a particular period of time (e.g., 10years) to comply with state or federal regulations, while similarregulations do not apply to the file system data. The compliance copyrule set 164 is associated with the same tape library 108B and mediaagent 144B as the disaster recovery copy rule set 162, although adifferent storage device or media agent could be used in otherembodiments. Finally, the compliance copy rule set 164 specifies thatcopies generated under the compliance copy rule set 164 will be retainedfor 10 years, and will be generated on a quarterly basis.

At step 1, the storage manager 140 initiates a backup operationaccording to the backup copy rule set 160. For instance, a schedulingservice running on the storage manager 140 accesses schedulinginformation from the backup copy rule set 160 or a separate schedulingpolicy associated with the client computing device 102, and initiates abackup copy operation on an hourly basis. Thus, at the scheduled timeslot the storage manager 140 sends instructions to the client computingdevice 102 to begin the backup operation.

At step 2, the file system data agent 142A and the email data agent 142Bresiding on the client computing device 102 respond to the instructionsreceived from the storage manager 140 by accessing and processing theprimary data 112A, 112B involved in the copy operation from the primarystorage device 104. Because the operation is a backup copy operation,the data agent(s) 142A, 142B may format the data into a backup format orotherwise process the data.

At step 3, the client computing device 102 communicates the retrieved,processed data to the first media agent 144A, as directed by the storagemanager 140, according to the backup copy rule set 160. In some otherembodiments, the information management system 100 may implement aload-balancing, availability-based, or other appropriate algorithm toselect from the available set of media agents 144A, 144B. Regardless ofthe manner the media agent 144A is selected, the storage manager 140 mayfurther keep a record in the storage manager database 140 of theassociation between the selected media agent 144A and the clientcomputing device 102 and/or between the selected media agent 144A andthe backup copy 116A.

The target media agent 144A receives the data from the client computingdevice 102, and at step 4 conveys the data to the disk library 108A tocreate the backup copy 116A, again at the direction of the storagemanager 140 and according to the backup copy rule set 160. The secondarystorage device 108A can be selected in other ways. For instance, themedia agent 144A may have a dedicated association with a particularsecondary storage device(s), or the storage manager 140 or media agent144A may select from a plurality of secondary storage devices, e.g.,according to availability, using one of the techniques described in U.S.Pat. No. 7,246,207, which is incorporated by reference herein.

The media agent 144A can also update its index 153 to include dataand/or metadata related to the backup copy 116A, such as informationindicating where the backup copy 116A resides on the disk library 108A,data and metadata for cache retrieval, etc. After the 30 day retentionperiod expires, the storage manager 140 instructs the media agent 144Ato delete the backup copy 116A from the disk library 108A.

At step 5, the storage manager 140 initiates the creation of a disasterrecovery copy 116B according to the disaster recovery copy rule set 162.For instance, at step 6, based on instructions received from the storagemanager 140 at step 5, the specified media agent 144B retrieves the mostrecent backup copy 116A from the disk library 108A.

At step 7, again at the direction of the storage manager 140 and asspecified in the disaster recovery copy rule set 162, the media agent144B uses the retrieved data to create a disaster recovery copy 116B onthe tape library 108B. In some cases, the disaster recovery copy 116B isa direct, mirror copy of the backup copy 116A, and remains in the backupformat. In other embodiments, the disaster recovery copy 116C may begenerated in some other manner, such as by using the primary data 112A,112B from the storage device 104 as source data. The disaster recoverycopy operation is initiated once a day and the disaster recovery copies116A are deleted after 60 days.

At step 8, the storage manager 140 initiates the creation of acompliance copy 116C, according to the compliance copy rule set 164. Forinstance, the storage manager 140 instructs the media agent 144B tocreate the compliance copy 116C on the tape library 108B at step 9, asspecified in the compliance copy rule set 164. In the example, thecompliance copy 116C is generated using the disaster recovery copy 116B.In other embodiments, the compliance copy 116C is instead generatedusing either the primary data 112B corresponding to the email sub-clientor using the backup copy 116A from the disk library 108A as source data.As specified, compliance copies 116C are created quarterly, and aredeleted after ten years.

While not shown in FIG. 1E, at some later point in time, a restoreoperation can be initiated involving one or more of the secondary copies116A, 116B, 116C. As one example, a user may manually initiate a restoreof the backup copy 116A by interacting with the user interface 158 ofthe storage manager 140. The storage manager 140 then accesses data inits index 150 (and/or the respective storage policy 148A) associatedwith the selected backup copy 116A to identify the appropriate mediaagent 144A and/or secondary storage device 116A.

In other cases, a media agent may be selected for use in the restoreoperation based on a load balancing algorithm, an availability basedalgorithm, or other criteria. The selected media agent 144A retrievesthe data from the disk library 108A. For instance, the media agent 144Amay access its index 153 to identify a location of the backup copy 116Aon the disk library 108A, or may access location information residing onthe disk 108A itself.

When the backup copy 116A was recently created or accessed, the mediaagent 144A accesses a cached version of the backup copy 116A residing inthe media agent index 153, without having to access the disk library108A for some or all of the data. Once it has retrieved the backup copy116A, the media agent 144A communicates the data to the source clientcomputing device 102. Upon receipt, the file system data agent 142A andthe email data agent 142B may unpackage (e.g., restore from a backupformat to the native application format) the data in the backup copy116A and restore the unpackaged data to the primary storage device 104.

Exemplary Secondary Copy Formatting

The formatting and structure of secondary copies 116 can vary, dependingon the embodiment. In some cases, secondary copies 116 are formatted asa series of logical data units or “chunks” (e.g., 512 MB, 1 GB, 2 GB, 4GB, or 8 GB chunks). This can facilitate efficient communication andwriting to secondary storage devices 108, e.g., according to resourceavailability. For example, a single secondary copy 116 may be written ona chunk-by-chunk basis to a single secondary storage device 108 oracross multiple secondary storage devices 108. In some cases, users canselect different chunk sizes, e.g., to improve throughput to tapestorage devices.

Generally, each chunk can include a header and a payload. The payloadcan include files (or other data units) or subsets thereof included inthe chunk, whereas the chunk header generally includes metadata relatingto the chunk, some or all of which may be derived from the payload. Forexample, during a secondary copy operation, the media agent 144, storagemanager 140, or other component may divide the associated files intochunks and generate headers for each chunk by processing the constituentfiles.

The headers can include a variety of information such as fileidentifier(s), volume(s), offset(s), or other information associatedwith the payload data items, a chunk sequence number, etc. Importantly,in addition to being stored with the secondary copy 116 on the secondarystorage device 108, the chunk headers can also be stored to the index153 of the associated media agent(s) 144 and/or the storage managerindex 150. This is useful in some cases for providing faster processingof secondary copies 116 during restores or other operations. In somecases, once a chunk is successfully transferred to a secondary storagedevice 108, the secondary storage device 108 returns an indication ofreceipt, e.g., to the media agent 144 and/or storage manager 140, whichmay update their respective indexes 150, 153 accordingly.

During restore, chunks may be processed (e.g., by the media agent 144)according to the information in the chunk header to reassemble thefiles. Additional information relating to chunks can be found in U.S.Pat. No. 8,156,086, which is incorporated by reference herein.

Example Virtualized Systems Including Proxies for Performing StorageOperations

FIGS. 2A-2C are block diagrams illustrative of embodiments of respectivestorage systems 200, 218, 228, each including a proxy computing device204 (also referred to as proxy client 204) communicating with at leastone storage device 208 on behalf of at least one client computing device206, 220, 230.

FIG. 2A is a block diagram illustrative of an embodiment of a storagesystem 200. The system 200 includes a storage manager 202, a proxyclient computing device 204, at least one virtual client computingdevice 206 (also referred to as virtual client 206), and a storagedevice 208. The proxy client 204 communicates with the storage device208 on behalf of virtual client(s) 206. The components of the storagesystem 200 communicate with each other via any appropriate type ofnetwork, including wired or wireless networks including, but not limitedto a SAN, LAN, WAN, the internet, etc. In some embodiments, the systemcan further include a proxy client storage device 205. In certainembodiments, the proxy client storage device 205 is local to the proxyclient 204, while the storage device 208 is remotely located.Furthermore, the proxy client storage device 205 can store data that isnot stored in the storage device 208 and that is accessible by the proxyclient 204 and/or virtual clients 206. For example, the proxy clientstorage device 205 can store executable files, system files, applicationfiles, and other files that are selected to not be stored in the storagedevice 208. Accordingly, during backup operations in certainembodiments, the data stored in the proxy client storage device 205 isnot backed up to the storage device 208. In some embodiments, a subsetof the files stored in the proxy client storage device 205 are backed upor otherwise copied to the storage device 208.

The storage manager 202 can generally be configured to coordinatestorage operations, and invokes the other modules to implement storageoperations, e.g., according to a storage policy. The storage manager 202can be similar to or the same as the storage manager 140 of FIGS. 1A-1E.Similarly, the proxy client 204 and virtual client(s) 206 may be similarto or the same as the client computing device 102 described previouslywith respect to FIGS. 1A-1E. For example, the proxy client 204 andvirtual clients 206 can include one or more data agents 210, 212,respectively. In the illustrative embodiment of FIG. 2A, the proxyclient 204 is a host computing device, and includes one or more of thevirtual clients 206 instantiated thereon. For instance, the proxy client204 may have a virtual machine manager (VMM) (not shown) instantiatedthereon, which may also be referred to as a hypervisor. The VMM canimplement a hardware virtualization allowing the virtual clients 206 torun concurrently on the host computer. The proxy client 204 may also bereferred to herein interchangeably as one or more of a proxy device,proxy computing device, host, or host computing device.

The VMM, in certain embodiments, generally operates as a supervisoryprogram, presenting the virtual clients 206 a virtual operating platformand managing execution of the virtual clients 206. For instance, thevirtual clients 206 may comprise guest operating systems runningconcurrently on the proxy client 204. The operating systems associatedwith the virtual clients 206 can be the same type of operating system asthe operating system that is running on the proxy client 204. Or, inother configurations, the operating system associated with one or moreof the proxy clients 206 may be of a different type than the operatingsystem running on the proxy client 204. Moreover, while each of thevirtual clients 206 may have the same type of associated operatingsystem in some cases, in other embodiments, one or more of the virtualclients 206 has a different associated operating system than one or moreof the other virtual clients 206. The specific types of operatingsystems executing on the proxy client 204 and the virtual clients 206can vary. For instance, depending on the configuration, one or more ofthe following, or other operating systems can be used: MicrosoftWindows, Unix, Linux, Mac OS X, Android, iOS and z/OS.

In some embodiments, such as where the proxy client 204 and the virtualclients 206 run the same type of operating system, the virtual clients206 comprise operating system-level virtualizations. In such cases, eachof the virtual clients 206 forms an isolated user-space instance. Forinstance, each of the virtual clients 206 can act as an isolated virtualserver (e.g., a zone, such as a Solaris Zone) within the singleoperating system that is running on the proxy client 204. In one suchembodiment, the virtual clients each implement containers (e.g., SolarisContainers), where each container forms a combination of system resourcecontrols and boundary separation, provided by zones, for example.

Each of the virtual clients 206 can further include one or more dataagents 212. In some embodiments the virtual clients 206 do not havedirect access to the storage device 208. Thus, as will described ingreater detail, the virtual clients 206 communicate with the storagedevice 208 indirectly via the proxy client 204.

The storage device 208 can include one or more storage devices of anyappropriate type (e.g., hard-drive, tape, solid state, etc.) and can bea local storage device of the proxy client 204 or remote from the proxyclient 204, depending on the embodiment.

In some embodiments, the storage device 208 is capable of performingsnapshot operations. And in some cases, the storage device 208 performsthe snapshot operations substantially independently, using hardware,firmware and/or software residing on the storage device 208. Forinstance, the storage device 208 may be capable of performing snapshotoperations upon request, without intervention or oversight from any ofthe other components in the system 200. Where the storage device 208performs the snapshot operation in this self-contained fashion, withoutthe involvement of the proxy client 204 or other components in thesystem 200, the snapshot may be referred to as a “hardware snapshot”. Insome embodiments, the system 200 is capable of performing “softwaresnapshots” in which the proxy client 204 or other components in thesystem manage the snapshot operation. The storage device 208 is alsocapable of performing additional operations, such as, but not limitedto, logical unit number (LUN) provisioning, snapshot queries, mappingLUNs to a host, and running storage reports for clients.

The proxy client 204 can be in communication with the storage device 208over a network (e.g., a LAN or WAN). Furthermore, the storage device 208can include sufficient storage capacity to serve the needs of not onlythe proxy client 204, but also the hosted virtual clients 206. Thememory space of the storage 208 can be allocated amongst the variousclients such that separate portions are dedicated to each virtual client206 and to the proxy client 204. Furthermore, the storage device 208 canstore primary and/or secondary copies of data associated with the proxyclient 204 and virtual client 206. In some embodiments, the storagedevice 208 is similar to the primary storage device 104 of FIGS. 1A-1E.In certain embodiments the storage device is similar to the secondarystorage device 108 of FIG. 1. In yet further embodiments, the storagedevice 208 is similar to primary storage device 104 and/or secondarystorage device 108 of FIGS. 1A-1E.

Because the virtual clients 206 do not have direct access to the storagedevice 208, the proxy client 204 is used to interface with the storagedevice 208 to perform certain storage operations on behalf of thevirtual clients 206. The storage operations can include, but are notlimited to, the creation of a snapshot, the mounting and un-mounting ofa snapshot, and reversion to a particular snapshot. For example, if astorage policy dictates that a snapshot is to be taken of dataassociated with the one of the virtual clients 206 (e.g., of the entirefile system, or of select directories, folders or files associated withthe virtual client 206), the storage manager 202 instructs theappropriate data agent(s) 212 on the virtual client 206 to perform thesnapshot operation. In one embodiment, the storage manager 140 instructsthe Microsoft Exchange data agent 212 to perform a snapshot of certainMicrosoft Exchange production data of the virtual client 206. The dataagent 212 forwards the snapshot request to an appropriate data agent 210or other component of the proxy client 204. In turn, the proxy client204 forwards the request to create the snapshot to the storage device208 on behalf of the virtual client 206.

In response to the request, the storage device 208 creates a snapshot ofthe desired virtual client data. The snapshot may reside in a portion ofthe storage device 208 dedicated to storing data for the particularvirtual client 206, for example. Or the storage device 208 may insteadallocate space for snapshot requests in some other manner, e.g., basedon an allocation policy maintained by the storage device 208.

Similarly, when the virtual client 206 desires to mount a previouslyunmounted or unknown snapshot, the virtual client 206 can request themounting of the data from the data agent 210 of the proxy client 204. Inturn, the proxy client 204 requests the mounting data, or disk arraydata from the storage device 208. Upon retrieving the disk arrayinformation of the snapshot, the storage device 208 transmits the datato the proxy client 204. The proxy client transmits the data to thevirtual client 206 and the virtual client is then able to mount and/oraccess the snapshot as desired.

FIG. 2B is a block diagram illustrative of an embodiment of a storagenetwork environment 218 including a proxy client communicating with astorage device 208 on behalf of a client computing device 220 (alsoreferred to as client 220). The storage manager 202, proxy client 204and storage device 208 can be similar to or the same as thecorresponding components described previously with respect to FIG. 2A.However, the client 220 of FIG. 2B is different from the virtual client206 of FIG. 2A. For example, the client 220 can be a distinct,non-virtual, physical device, separate from the proxy client 204, suchas a personal computer, workstation, server, etc. Although notillustrated in FIG. 2B, the clients 220 can include their own storagedevices similar to the proxy client storage device 205, described ingreater detail above with reference to FIG. 2A. In addition, the client220 can in some cases have direct access to the storage device 208 forperforming certain functions. However, in some embodiments, the client220 uses the proxy client 204 to perform one or more other functions,including storage operations (e.g., snapshots), for example. In someembodiments, the client 220 does not have direct access to the storagedevice 208, and only communicates with the storage device 208 via theproxy client 204. For example, in some instances it is desirable to giveonly a single client direct access to the storage device 208, e.g., forperforming certain storage operations (e.g., snapshots), such as where asecurity policy dictates such an arrangement. In this way, the securityof the storage device can be maintained, and the likelihood of errors orproblems occurring during storage operations can be decreased.

Storage operations can include, but are not limited to, creating asnapshot of the client 220, mounting the snapshot information to theclient 220, and/or reverting to a previous snapshot of the client 220.In some embodiments, the storage manager 202 can transmit a snapshotcreation command to the client 220. Using the data agent 222, the clientcan request that the proxy client 204 perform the snapshot creation. Theclient 220 can make the request from the proxy client 204 via the dataagent 210 of the proxy client 204. Upon receiving the snapshot creationrequest, the proxy client 204 can request that the snapshot be createdin the storage device 208, as described in greater detail below withreference to FIGS. 3A and 5. Similarly, the client 220 can request theproxy client 204 to retrieve snapshot location information and/or otherdisk data, and request a reversion of a previous snapshot.

FIG. 2C is a block diagram illustrative of an embodiment of a storagenetwork environment 228 including a proxy client 204 communicating witha storage device 208 on behalf of a virtual client computing device 230(also referred to as virtual client 230). The storage manager 202, proxyclient 204 and storage device 208 can be similar to or the same as thecorresponding components described previously with respect to FIGS. 2Aand 2B. Furthermore, although not illustrated in FIG. 2B, the proxyclient 204 and virtual clients 230 can include their own storage devicessimilar to the proxy client storage device 205, described in greaterdetail above with reference to FIG. 2A. The virtual client 230 can besimilar to or the same as the corresponding components can be similar toor the same as the virtual client 206 of FIG. 2A, however, the virtualclient 230 is not instantiated in the proxy client 204, as is thevirtual client 206 of FIG. 2A.

Furthermore, unlike the configurations of FIGS. 2A and 2B, theembodiment of FIG. 2C additionally includes a server 234 that is indirect communication with the storage device 208 and is also in directcommunication with the proxy client 204 and the virtual client 230.However, in some embodiments, the virtual clients 230 are not providedwith direct access to the storage device 208. For instance, as indicatedby the dashed line, the virtual client 230 may communicate with thestorage device 208 indirectly via the server 234. In such a situation,the server 234 generally acts as a proxy for the virtual client 230 inrelation to interaction with the storage device 208. Or, the virtualclient 230 may instead request that a storage operation be performed inthe storage device by communicating the request to the proxy client 204.In some embodiments, the data agent 232 of virtual client 230communicates with the data agent 210 of the proxy client 204 tocommunicate the storage operation request. In turn, the proxy client 204relays the request to the server 234, which forwards the request on tothe storage device 208.

The storage device 208 receives the request and performs the desiredstorage operation. Upon completion of the storage operation, the storagedevice 208 transmits relevant information indicating that the storageoperation has been completed to the server 234, which forwards theinformation to the proxy client 204 (or directly to the virtual client230, depending on the embodiment). The proxy client 204 thereaftertransmits the relevant data to the virtual client 230. As described ingreater detail above, once the virtual client 230 receives confirmationof the completion of the storage operation, the virtual client 230 cannotify the storage manager 202 that the storage operation has beencompleted, and/or perform one or more additional steps using therelevant data received. For example, the virtual client 230 can usesnapshot disk data (e.g., location information) to mount a snapshot tothe virtual client 230.

FIGS. 3A and 3B are state diagrams illustrative of example interactionbetween the various components of the storage network environment 200 ofFIG. 2A. For purposes of simplicity, the proxy client storage device205, described in greater detail above with reference to FIG. 2A, is notshown. Although FIGS. 3A and 3B are directed towards the storage networkenvironment 200 illustrated in FIG. 2A, certain aspects of the statediagrams are compatible with the environments shown in FIGS. 2B and 2C.For instance, similar state diagrams may be illustrative of theinteraction between the various components of the storage networkenvironments of FIGS. 2B and 2C. Thus, the state diagrams illustrated inFIGS. 3A and 3B should not be construed as limiting.

FIG. 3A is a state diagram illustrative of the interaction between thevarious components of the storage network environment 200 to perform astorage operation (e.g., a snapshot). As illustrated, the storagemanager 202 (1) transmits a storage operation command to the data agent212 of the virtual client 206. As mentioned previously, the storageoperation command can include any number of different storageoperations, such as a snapshot creation, a mounting of a snapshot to thevirtual client, a reversion to a previous snapshot, and the like. Uponreceiving the storage operation command, the virtual client 206determines that it is unable to initiate the storage operation by itselfdirectly sending the storage operation request to the storage device208, and (2) transmits a storage operation request to the data agent 210of the proxy client 204. Although illustrated as the data agent 212communicating via the data agent 210, the virtual client 206 cancommunicate with the proxy client 204 in any appropriate manner.

The storage operation request can include the information to perform thestorage operation, and/or for the proxy client 204 to properly initiatethe request to the storage device 208 on behalf of the virtual client206. For example, the storage operation request can include informationregarding the particular portion within the storage device 208 thatcontains the virtual client 206 data, such as one or more addresslocations or ranges of address locations within the storage device 208.In certain embodiments, the proxy client 204 uses the information fromthe storage operation request to determine the portion within thestorage device 208 that is associated with the data of the virtualclient 206. For example, the proxy client 204 can use identifyinginformation relating to the virtual client 206 (e.g., client ID) todetermine those portions of the storage 208 that contain data associatedwith the virtual client 206. The proxy client 204 (3) transmits thestorage operation request to the storage device 208.

Upon receiving the storage operation request, the storage device 208 (4)performs the requested storage operation. Upon completion of the storageoperation, the storage device 208 (5) notifies the proxy client 204 thatthe storage operation has been completed. The proxy client 204 (6)transmits relevant data to the data agent 212 of the virtual client 206.In some embodiments, the proxy client 204 transmits the relevant datausing the data agent 210. The relevant data can include any and allinformation to be used by the virtual client 206 to perform one or moreoperations, and to notify the storage manager 202. In some embodiments,the relevant data can include data requested by the data agent 212and/or data not requested by the data agent 212. Upon receiving the datafrom the proxy client 204, the virtual client 206 (7) notifies thestorage manager 202 that the storage operation has been completed.

FIG. 3A further illustrates an embodiment of the portion of the storagedevice 208 associated with the virtual client 206 that includes thevirtual client's data and snapshots of the virtual client′ data. Theportion of the storage device containing the virtual client's data canbe an addressable space of the storage device and can include contiguousor non-contiguous addresses. In the illustrated embodiment, the portionof the storage device 208 that is associated with the virtual client 206is labeled virtual client storage 310. The virtual client storage 310may store an initial copy of the virtual client's data, backup copies,and/or snapshots. In some embodiments, snapshots of the virtual client'sdata, or virtual client snapshots 312, can reside in the same ordifferent portion of the storage device 208 as the virtual clientstorage 310.

Upon receiving a snapshot creation request, the storage device 208performs a snapshot 312 of the virtual client storage 310 containedwithin the storage device 208. The storage device 208 creates thevirtual client snapshot 312 based on the snapshot request and/or on thedata stored in the virtual client storage 310. For instance, thesnapshot 312 may comprise a set of pointers to the first portion 310 forun-modified virtual client data, as well as actual data copies formodified virtual client data, according to a copy-on-write scheme, forexample. Upon completion of the snapshot creation, the storage device208 notifies the proxy client 206 that the snapshot has been created.

The proxy client 204 transmits a snapshot identifier to the virtualclient 206. The virtual client 206 can use the snapshot identifier toaccess the snapshot or at least to verify that the snapshot has beencreated. For example, the virtual client 206 can include the snapshotidentifier of a particular snapshot as part of a request (e.g., accessrequests, reversion requests, etc.) made to the proxy client 204. Thesnapshot identifier can contain location information regarding theportion of memory within the storage device 208 that contains theparticular snapshot and/or the proxy client 204 can include a look-uptable to determine the portion of memory within the storage device 208that includes the particular snapshot. Once the virtual client receivesthe snapshot identifier, or other relevant data, the virtual client 206can notify the storage manager 202 that the snapshot has been created.

FIG. 3B is a state diagram illustrative of the interaction between thevarious components of the storage network environment when the storagemanager 202 issues a snapshot mount command. As illustrated in FIG. 3B,the storage manager 202 (1) transmits a snapshot mount command to thevirtual client 206. The snapshot mount command can provide sufficientinformation such that the virtual client 206 can request that a snapshotbe mounted to the virtual client 206. For example, the snapshot mountcommand can include the snapshot identifier of the snapshot to bemounted, etc. In some embodiments, the snapshot mount command can beincluded as part of a request to access or read a snapshot previouslycreated for the virtual client 206. Upon receiving the snapshot mountcommand, and determining that the virtual client 206 does not alreadyhave access to the snapshot, the virtual client 206 (2) requests thedisk data (e.g., location information) of the virtual client snapshot312 from the proxy client 204. The disk data of the virtual clientsnapshot 312, or snapshot disk data, can include location information,such as an address, array, partition, block, tape location, cluster,etc., regarding where the virtual client snapshot 312 is located. Asmentioned previously, the virtual client 206 and proxy client 204 cancommunicate via their respective data agents 212, 210.

The proxy client 204 can use the information related to the virtualclient, such as a virtual client identifier and/or a snapshotidentifier, to identify the virtual client storage 310 and (3) requestthe location information and/or other disk data of the virtual clientsnapshot 312. The storage device 208 can use the received information toidentify and (4) retrieve the snapshot location information and/or otherdisk data of the virtual client snapshot 312.

Upon identifying and retrieving the snapshot disk data of the virtualclient snapshot 312, the storage device 208 (5) transmits the snapshotlocation information and/or other disk data to the proxy client 204. Thesnapshot location information and/or other disk data can then be (6)transmitted from the proxy client 204 to the virtual client 206. Uponreceiving the snapshot disk data, the virtual client 206 can performadditional processes involving the location information and/or otherdisk data. For example, the virtual client 206 can (7) mount thesnapshot, thereby allowing the virtual client 206 to have access to thedata contained within the virtual client snapshot 312. Upon mounting thesnapshot, the virtual client 206 can (8) notify the storage manager 202that the snapshot mount operation has been completed.

As mentioned previously, although FIGS. 3A and 3B are directed to statediagrams illustrative of the interaction between the various componentsof the storage network environment illustrated in FIG. 2A, it is to beunderstood that similar diagrams can be made for FIGS. 2B and 2C. Forpurposes of brevity, however, such diagrams have been omitted. Theadditional diagrams can be made with similar features and may containvariations. For example, a state diagram illustrating the interactionbetween the components of the illustrative embodiment of FIG. 2C cancontain additional steps illustrating the interaction between proxyclient 204, server 234, and storage device 208. For example, requestsfrom the client 204 can be sent to the server 234 and forwarded to thestorage device 208. Similarly data from the storage device 208 can betransmitted to the server 234 and on to the proxy client 204. One ofordinary skill in the art will understand the various embodiments andmodifications that can be made to the state diagrams 3A and 3B in orderto illustrate the interaction between the components of the illustrativeembodiments of FIGS. 2B and 2C.

FIGS. 4-7 are flow diagrams illustrative of embodiments of routinesimplemented by a proxy client for requesting a storage device to performone or more storage operations.

FIG. 4 is a flow diagram illustrative of an embodiment of a routine 400implemented by a client proxy for requesting a storage device to performone or more storage operations. One skilled in the relevant art willappreciate that the elements outlined for routine 400 can be implementedby one or more computing devices/components that are associated with theproxy client 204. Accordingly, routine 400 has been logically associatedas being generally performed by the proxy client 204. However, thefollowing illustrative embodiment should not be construed as limiting.

At block 402, the proxy client receives a storage operation request fora client. The storage operation request can be received from a clientsuch as a virtual client or a separate client device, or can be receivedfrom a storage manager on behalf of a client. Furthermore, a storageoperation request can include a request to perform, or have performed,one or more storage operations. For example the storage operationrequest can include, but is not limited to any one or more of a snapshotcreation, snapshot mount, and/or a reversion to a previous snapshot. Thestorage operation request can be received at regular intervals asdetermined by a storage policy, and can be received from the client, thestorage manager, some other computing device and/or a user via wired orwireless communication protocols. In some embodiments, the clients donot have direct access to a storage device storing the data of theclients. In certain embodiments, the clients have limited access to thestorage device, but do not have direct access to the storage device forrequesting one or more storage operations.

At block 404, the proxy client 204 transmits the storage operationrequest to a storage device. As mentioned previously, the storage devicecan include one or more disk arrays storing data related to the clientsand the proxy client. In some embodiments, prior to transmitting thestorage operation request, the proxy client 204 uses informationregarding the client to determine the storage device and location withinthe storage device where the data associated with the client is stored,and transmits this information to the storage device.

At block 406, the proxy client receives an indication of the completionof the storage operation from the storage device. The indication caninclude various pieces of information that can be used to verify thatthe storage operation has been completed. For example, the indicationcan include a snapshot identifier when a snapshot is created, a snapshotdisk identifier when a snapshot is to be mounted to a client, and/orsome other identifier when other storage operations are used.

At block 408, the proxy client transmits relevant data to the client.The relevant data can include any one or more identifiers received fromthe storage device that can be used by the client to verify that thestorage operation has completed successfully. Furthermore the relevantdata can include additional information that can be used by the clientto perform additional processes based on the identifiers received fromthe proxy client 204.

Additional, fewer, or different blocks can be used to implement theprocess 400 without departing from the spirit and scope of thedescription. For example, in some embodiments the client can perform oneor more processes using the relevant data received from the proxyclient. Furthermore, although not illustrated, the storage manager cantransmit a storage operation command to the client, which in turn cantransmit a storage operation request to the proxy client.

FIG. 5 is a flow diagram illustrative of an embodiment of a routine 500implemented by the client proxy 204 for requesting a snapshot creationfrom a storage device. One skilled in the relevant art will appreciatethat the elements outlined for routine 500 can be implemented by one ormore computing devices/components that are associated with the clientproxy 204. Accordingly, routine 500 has been logically associated asbeing generally performed by the proxy client 204. However, thefollowing illustrative embodiment should not be construed as limiting.

At block 502, the proxy client 204 receives a snapshot request from aclient. As mentioned previously, the client can be a virtual clientinstantiated on the proxy client 204, a virtual client instantiated on aserver or other device, or a distinct client separate from the proxyclient 204. The snapshot request can be received at regular intervals asdetermined by a storage policy, and can be received from the client, thestorage manager, some other computing device and/or a user via wired orwireless communication protocols.

At block 504, the proxy client 204 transmits a snapshot request to astorage device 208. As mentioned previously, prior to transmitting thesnapshot request, the proxy client 204 can identify one or more portionsof the storage device 208 that contain the data associated with theclient and transmit that data with the snapshot request.

Upon receiving the snapshot request, the storage device 208 performs thesnapshot creation by performing a snapshot of the portion of the storagedevice 208 that includes the data from the client. The storage device208 can generate a snapshot identifier for the created snapshot. Thesnapshot identifier can be a number, can be any alphanumeric symbol orother number or symbol used to uniquely identify the snapshot that iscreated by the storage device.

At block 506, the proxy client 204 receives the snapshot identifier fromthe storage device identifying the snapshot that has been created. Atblock 508, the proxy server transmits the relevant snapshot data to theclient. The relevant snapshot data can include the snapshot identifierreceived from the storage device or additional information, such as timeand date information or other information that can be used by the clientto identify the snapshot that is created by the storage device and/orotherwise process the data.

Additional, fewer, or different blocks can be used to implement theprocess 500 without departing from the spirit or scope of thedescription. For example, the proxy client 204 can notify the storagemanager directly that the snapshot has been created. In someembodiments, the proxy client 204 receives a notification that asnapshot has been created and generates the snapshot identifier for theclient. In certain embodiments, the client generates the snapshotidentifier and transmits it along with the snapshot request or afterreceiving the relevant data associated with the created snapshot.

FIG. 6 is a flow diagram illustrative of an embodiment of a routine 600implemented by a client proxy 204 for requesting a snapshot mount of asnapshot to be mounted to a client. One skilled in the relevant art willappreciate that the elements outlined for routine 600 can be implementedin one or more computing/components that are associated with the proxyclient 204. Accordingly, routine 600 has been logically associated asbeing generally performed by the proxy client 204. However, thefollowing illustrative embodiment should not be construed as limiting.

At block 602, the proxy client 204 receives a request to mount aparticular snapshot to a client. The particular snapshot can be asnapshot that was previously created by a storage device 208. In someembodiments, the request can be a request to review or read from apreviously created snapshot. The request can be received from a storagemanager 202, a user, and/or directly from a client, such as virtualclient 206, client 220, and/or virtual client 230.

At block 604, the proxy client 204 requests disk information (e.g.,location information) of the particular snapshot that is to be mountedto the client from the storage device. The disk information requestedcan include a disk sector, array, partition, block, tape location, orother location information. In turn, the storage device can retrieve thelocation information and/or other disk data associated with the snapshotand transmit the location information and/or other disk data to theproxy client 204, as illustrated in block 606. As mentioned previously,the disk information can include location information as to the locationwithin the data storage where the snapshot is located. Furthermore uponrequesting the disk information associated with the snapshot from thestorage device, the proxy client 204 can provide one or more snapshotidentifiers to the storage device.

At block 608 the proxy client 204 transmits the disk information (e.g.,location information) received from the storage device to the client.Additional, fewer, or different blocks can be used to implement theprocess 600 without departing from the spirit and scope of thedescription. For example, the client can use the disk information tomount the snapshot to itself and/or access the snapshot data.Furthermore, the client can notify the storage manager that the snapshothas been mounted. In addition, the client can unmount the snapshot asdesired.

FIG. 7 is a flow diagram illustrative of an embodiment of routine 700implemented by a client proxy for requesting a storage device to revertto a previous snapshot. One skilled in the relevant art will appreciatethat the elements outlined for routine 700 can be implemented by one ormore computing devices/components that are associated with the clientproxy 204. Accordingly, routine 700 has been logically associated asbeing generally performed by the client proxy 204. However, thefollowing illustrative embodiment should not be construed as limiting.

At block 702, the proxy server receives a reversion request. Asmentioned previously the reversion request can be received from clients,such as the virtual client 206, client 220, and virtual client 230, thestorage manager 202, other storage managers, users, computing devices,and the like. A reversion request can include the information regardinga specific snapshot that is to be used to revert the data in the storagedevice 208. For example, this reversion request can include anidentifier of the specific snapshot that should be used for thereversion. The identifier can include location information, time and/orchronological information, and the like.

At block 704, the proxy client 204 transmits the reversion request tothe storage device 208. Using the information received in the reversionrequest, the storage device 208 is reverts the data related to theclient to a previous version. At block 706, the proxy client 204receives verification from the storage device 208 that the data has beenreverted.

At block 708, the proxy client 204 transmits relevant reversion data tothe client 708. The relevant reversion data can include an identifier ofthe snapshot used for the reversion, as well as additional informationconcerning the new state of the data in the storage device 208, whichsnapshot was used, the date and time of the reversion, additionalsnapshots that may be used for additional reversions, and the like.

Additional, fewer or different blocks can be used to implement theprocess 700 without departing from the spirit and scope of thedescription. For example the client proxy can notify the storage manager202 that the data has been reverted.

Example System Including Proxy Media Agent

FIG. 8 is a block diagram illustrative of an embodiments of a storagesystem 118, which includes a storage manager 802, one or more proxymedia agents 804, one or more storage devices 808, and one or moreclients 806. The components of the storage system 800 communicate witheach other via any appropriate type of network, including wired orwireless networks including, but not limited to a SAN, LAN, WAN, theinternet, etc.

Generally speaking, the components of system 118 can be similar to orthe same as the similarly named components of FIG. 1A-1E. For example,the storage manager 802 can generally be configured to coordinatestorage operations, and invoke the other modules to implement storageoperations, (e.g., according to a storage policy) similar to the storagemanager 140 of FIG. 1C. In the illustrated embodiment of FIG. 8, eachclient 806 includes an associated media agent 820 and one or more dataagents 832. For instance, each client 806 may comprise a separatecomputing device having a media agent 820 and one or more data agents832 installed thereon. It will be understood that additional mediaagents that are separate from the media agents 820 of the client can beincluded as part of the system 118. In addition, in some embodiments,the client computing devices 806 do not include a media agent residingthereon, but instead communicate and are associated with media agentsinstalled on separate machines in an environment similar to the system118 described above with reference to FIGS. 1D-1E.

The system 118 can include one or more proxy media agents 804, which canfunction similar to the media agents 144 as described above in FIGS.1A-1E, and also communicate with the storage device 808 on behalf ofother media agents 820/clients 806. In some embodiments, the proxy mediaagents 804 can be configured to authenticate with the storage device 808and perform other control functionality for carrying out storageoperations on the storage device 808. The storage device 808 cangenerally include any type of appropriate storage media, and in someembodiments comprises a storage device capable of performing hardwaresnapshots. As a few non-limiting examples, the storage device 808 caninclude any of the following storage array products: EMC Clariion, EMCSymmetrix, EMC Celerra, Dell EqualLogic, IBM XIV, NetApp FAS, and HPEVA, and HP 8PAR disk arrays.

In some cases, the media agents 820 can have direct access to thestorage device 808 for performing certain functions, such as readingdata from the storage device 808 or transmitting data to the storagedevice 808. However, in some embodiments, the media agent 820 relies ona proxy media agent 804 to perform control functions, includingauthentication with the storage device and/or initiation/management ofcertain storage operations (e.g., snapshots), for example. Thus, incertain embodiments, the proxy media agents 804 are used only forcertain storage operations, such as snapshots, while other storageoperations, such as read/write are performed by the media agent 820.

In some embodiments, the media agent 820 does not have direct control ofthe storage device 808, and instead communicates with the storage device808 via the proxy media agent 804. For example, in some instances it isdesirable to give a relatively few number of media agents directaccess/control to the storage device 808, e.g., for performing certainstorage operations (e.g., snapshots), such as where a security policydictates such an arrangement. By providing a centralized point of accessto the storage device 808 through the proxy media agent(s) 804, the datastorage system can provide straightforward integration with a variety ofstorage devices 808.

Storage operations can include, but are not limited to, creating asnapshot of data associated with the client 806, mounting/unmounting asnapshot on the client 806, and/or reverting to a previous snapshot. Insome embodiments, the storage manager 802 can transmit a snapshotcreation command to the client 806. Using the data agent 832, the client806 can send the appropriate snapshot data (e.g., information relatingto the volume or other client data set to snap) to the media agent 820for storage in the storage device 808. As the media agent 820 may nothave control access to the storage device 808, the media agent 820 canforward the snapshot data to the proxy media agent 804. Upon receivingthe snapshot data, the proxy media agent 804 requests that the storagedevice 808 perform the snapshot creation operation. Similarly, for othertypes of snapshot operations, the proxy media agent 804 can act as acentralized intermediary for interacting with the storage device 808.For instance, the media agent 820 can request the proxy media agent 804to forward a request to retrieve a snapshot (e.g., for a mountoperation, snapshot location information, and/or other snapshotinformation from the storage device 808, or can forward a request torevert a snapshot back to the client device 806. In some embodiments,the proxy media agent 804 authenticates with the storage device 808 andinteracts with the storage device 808 for control purposes, but data istransmitted directly between the storage device 808 and the client 806,or between the storage device 808 and the media agent 820 associatedwith the client 806.

The storage device 808 receives the request and performs the desiredstorage operation. Upon completion of the storage operation, the storagedevice 808 transmits relevant information indicating that the storageoperation has been completed to the proxy media agent 804, whichforwards the information to the client 806 (e.g., to the media agent 820associated with the client). In embodiments where the media agent 820associated with the requesting client resides on a separate computingdevice it may forward the information received from the proxy mediaagent 804 to the client 806. As described in greater detail above, oncethe client 806 receives confirmation of the completion of the storageoperation, the client 806 can notify the storage manager 802 that thestorage operation has been completed, and/or perform one or moreadditional steps using the relevant data received. For example, theclient 806 can use retrieved information to mount a snapshot from thestorage device 808 to the client 806.

FIG. 9 is a state diagram illustrative of the interaction between thevarious components of the storage network environment 800 to perform astorage operation (e.g., to create a snapshot). As illustrated, thestorage manager 802 (1) transmits a storage operation command to theclient 806, such as to one of the data agents 832 residing on the client806. As one example, the scheduled snapshot is of a particular databasemaintained by a database application running on the client 806. Thus, acorresponding database data agent 832 residing on the client 806receives the snapshot creation request from the storage manager 802. Thedatabase data agent 832 may perform appropriate actions in conjunctionwith the snapshot operations, such as quiescing the database applicationduring the snapshot operation in order to maintain data integrity. Asmentioned previously, the storage operation command can include anynumber of different storage operations, such as a snapshot creation,mounting a previous snapshot, reversion to a previous snapshot, and thelike. Upon receiving the command, the client 806 (2) generates thestorage operation data. The storage operation data can include theinformation actual snapshot data, or identifiers of the snapshot datathat is to be stored in the storage device 808. For example, the client806 can perform a snapshot or other storage operation and/or generatedata relevant to the storage operation that can be used and/or stored bythe data storage device 808, such as location information, volumeinformation, etc.

The client 806 (e.g., the media agent 820) determines that the proxymedia agent 804 will be used and (3) transmits the storage operationrequest and associated data to the proxy media agent 804. For example,the client 806 (e.g., the media agent 820 associated with the client806) may forward to the proxy media agent 804 an instruction to preparefor or store snapshot data, as well as other information associated withthe snapshot (e.g., storage device identifier, an identifier or locationinformation associated with the data set that is being snapped, storagedevice group, etc.). In addition, the data agents 832 can communicatewith the media agent 820 to prepare the data for storage at the storagedevice 808.

Following receipt of the storage operation request and associated data,the proxy media agent 804 (4) authenticates with the storage device 808and transmits the storage operation request to the storage device 808.To authenticate with the storage device 808, the proxy media agent 804can maintain and transmit identifying information to the storage device808, such as username and password information, or other identifiers. Byauthenticating with the storage device 808, the proxy media agent 804can create a session for communicating with the storage device 808 andtransmitting the storage operation data. In some embodiments, the proxymedia agent 804 bundles storage operation data received from multipleclients prior to authenticating with the storage device.

Upon receiving the storage operation data, the storage device 808 (5)performs the requested storage operation. The requested storageoperation may include storing the storage operation data, such assnapshot data, and/or opening a communication channel, such as a channelto communicate with the media agent 820 associated with the requestingclient 806. In instances where a communication channel is opened, thestorage device 808 can receive and store data from the media agent 820or transmit data to the media agent 820 while the channel remains open.In this manner the proxy media agent 804 can be used for authenticationand control purposes while allowing data to be transmitted between thestorage device 808 and the client 806. Other communication mechanismscan be used as well.

Upon completion of the storage operation, the storage device 808 (6)notifies the proxy media agent 804 that the storage operation has beencompleted. In some embodiments, the notification indicates that acommunication channel has been opened for communication between thestorage device 808 and the media agent 820. In certain embodiments, thenotification indicates that the storage device 808 has completed thestorage operation (e.g., the snapshot is complete).

The proxy media agent 804 (7) transmits relevant data to the media agent820, which is communicated to the client 806. The relevant data caninclude any and all information to be used by the client 806 to performone or more operations, and to notify the storage manager 802 ofcompletion or other status related to the requested storage operation.In some embodiments, the relevant data can include data specificallyrequested by the media agent 820 and/or data not requested by the mediaagent 820. Upon receiving the data from the proxy media agent 804, theclient 806 (8) notifies the storage manager 802 that the storageoperation has been completed, or otherwise updates the storage manager802 regarding the status of the requested snapshot or other storageoperation. Some or all of the steps described can be repeated. Forexample, steps (3)-(7) can be repeated to store additional data relatingto one or more storage operations.

FIG. 10 is a flow diagram illustrative of an embodiment of a routineimplemented by a proxy media agent 804 for requesting a storage device808 to perform one or more storage operations. One skilled in therelevant art will appreciate that the elements outlined for routine 1000can be implemented by one or more computing devices/components that areassociated with the proxy media agent 804. Accordingly, routine 1000 hasbeen logically associated as being generally performed by the proxymedia agent 804. However, the following illustrative embodiment shouldnot be construed as limiting.

At block 1002, the proxy media agent 804 receives storage operation datafrom a media agent 820 on behalf of a client 806. The storage operationdata can include a request to perform, or have performed, one or morestorage operations, and or include data that is to be stored on thestorage device 808. For example the storage operation request caninclude, but is not limited to, any one or more of a snapshot creation,snapshot mount, and/or a reversion to a previous snapshot. The storageoperation request can be received at regular intervals as determined bya storage policy, and, depending on the embodiment, can be received bythe proxy media agent 804 from the media agent 820, the client 806, thestorage manager 802, some other computing device via wired or wirelesscommunication protocols. In some embodiments, the media agent 820associated with the requesting client device 806 and its associatedmedia agent 820 do not have direct access to the storage device 808. Forinstance, in certain embodiments, the media agents 820 have only limitedaccess to the storage device 808, such as a direct data connection, butdo not have the ability to control and access the storage device 808 forrequesting certain storage operations. For example, the media agents 820may be unable to authenticate with a storage device 808 and/or initiatehardware snapshot operations without the intervention of the proxy mediaagent 804.

At block 1004, the proxy media agent 804 transmits a storage operationrequest to the storage device 808. As mentioned previously, the storageoperation request can include a request to store to or retrieve datafrom the storage device 808 and/or request that a communication channelbe opened for communication between the media agent 820 and the storagedevice 808. The storage device 808 can include one or more disk arrays(e.g., hardware snapshot-capable disk arrays) storing data related tothe client 806, and can include any of the storage devices 808 describedherein.

At block 1006, the proxy media agent 804 receives an indication of thecompletion of the storage operation from the storage device. Theindication can include various pieces of information that can be used toverify that the storage operation has been completed. For example,depending on the type of storage operation, the indication can include asnapshot identifier for a newly created snapshot, a snapshot diskidentifier when a snapshot is to be mounted to a client, and/or someother identifier when other storage operations are used. In certainembodiments, the indication includes information regarding acommunication channel to allow the media agent 806 to communicate withthe storage device 808 and send/receive data from the storage device808.

At block 1008, the proxy media agent 804 transmits relevant data to theclient. The relevant data can include any one or more identifiersreceived from the storage device that can be used by the client toverify that the storage operation has completed successfully.Furthermore the relevant data can include additional information thatcan be used by the client to perform additional processes based on theidentifiers received from the proxy media agent 804.

Additional, fewer, or different blocks can be used to implement theprocess 1000 without departing from the spirit and scope of thedescription. For example, in some embodiments the client can perform oneor more processes using the relevant data received from the proxy mediaagent. Furthermore, although not illustrated, the storage manager cantransmit a storage operation command to the client, which in turn cantransmit a storage operation request to the proxy media agent.

Terminology

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or steps. Thus, such conditional language is notgenerally intended to imply that features, elements and/or steps are inany way required for one or more embodiments or that one or moreembodiments necessarily include logic for deciding, with or without userinput or prompting, whether these features, elements and/or steps areincluded or are to be performed in any particular embodiment.

Depending on the embodiment, certain acts, events, or functions of anyof the algorithms described herein can be performed in a differentsequence, can be added, merged, or left out all together (e.g., not alldescribed acts or events are necessary for the practice of thealgorithms). Moreover, in certain embodiments, acts or events can beperformed concurrently, e.g., through multi-threaded processing,interrupt processing, or multiple processors or processor cores or onother parallel architectures, rather than sequentially.

Systems and modules described herein may comprise software, firmware,hardware, or any combination(s) of software, firmware, or hardwaresuitable for the purposes described herein. Software and other modulesmay reside on servers, workstations, personal computers, computerizedtablets, PDAs, and other devices suitable for the purposes describedherein. Software and other modules may be accessible via local memory,via a network, via a browser, or via other means suitable for thepurposes described herein. Data structures described herein may comprisecomputer files, variables, programming arrays, programming structures,or any electronic information storage schemes or methods, or anycombinations thereof, suitable for the purposes described herein. Userinterface elements described herein may comprise elements from graphicaluser interfaces, command line interfaces, and other suitable interfaces.

Further, the processing of the various components of the illustratedsystems can be distributed across multiple machines, networks, and othercomputing resources. In addition, two or more components of a system canbe combined into fewer components. Various components of the illustratedsystems can be implemented in one or more virtual machines, rather thanin dedicated computer hardware systems. Likewise, the data repositoriesshown can represent physical and/or logical data storage, including, forexample, storage area networks or other distributed storage systems.Moreover, in some embodiments the connections between the componentsshown represent possible paths of data flow, rather than actualconnections between hardware. While some examples of possibleconnections are shown, any of the subset of the components shown cancommunicate with any other subset of components in variousimplementations.

Embodiments are also described above with reference to flow chartillustrations and/or block diagrams of methods, apparatus (systems) andcomputer program products. Each block of the flow chart illustrationsand/or block diagrams, and combinations of blocks in the flow chartillustrations and/or block diagrams, may be implemented by computerprogram instructions. Such instructions may be provided to a processorof a general purpose computer, special purpose computer, or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer orother programmable data processing apparatus, create means forimplementing the acts specified in the flow chart and/or block diagramblock or blocks.

These computer program instructions may also be stored in acomputer-readable memory that can direct a computer or otherprogrammable data processing apparatus to operate in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture including instruction meanswhich implement the acts specified in the flow chart and/or blockdiagram block or blocks. The computer program instructions may also beloaded onto a computer or other programmable data processing apparatusto cause a series of operations to be performed on the computer or otherprogrammable apparatus to produce a computer implemented process suchthat the instructions which execute on the computer or otherprogrammable apparatus provide steps for implementing the acts specifiedin the flow chart and/or block diagram block or blocks.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure. Indeed, the novel methods and systems describedherein may be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the describedmethods and systems may be made without departing from the spirit of thedisclosure. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the disclosure.

What is claimed is:
 1. A method for performing a storage operation usinga proxy secondary storage computing device, the method comprising:receiving at a first computing device a first request to perform a firstsnapshot operation, the first snapshot operation to be performed on afirst data set associated with one or more software applicationsexecuting on a second computing device, wherein the first computingdevice and the second computing device form part of a networked storagesystem comprising at least one storage device that is capable ofperforming snapshot operations; forwarding, using the first computingdevice, the first request to the storage device, wherein the storagedevice performs the first snapshot operation on the first data set inresponse to receipt of the first request; receiving, at the firstcomputing device, a first identifier associated with the snapshotoperation; and forwarding the first identifier to the second computingdevice.
 2. The method of claim 1, wherein the second computing devicecommunicates directly with the storage device for a first set of one ormore types of storage operations and communicates with the storagedevice via the first computing device for a second set of one or moretypes of storage operations.
 3. The method of claim 2, wherein the firstset includes data read operations and the second set includes one ormore snapshot operations.
 4. The method of claim 1, wherein the secondcomputing device is not in direct communication with the storage deviceand is only in indirect communication with the storage device via thefirst computing device.
 5. The method of claim 1, wherein the secondcomputing device does not have direct access to the storage device andonly indirectly accesses the storage device via the first computingdevice.
 6. The method of claim 1, wherein the first computing deviceauthenticates with the storage device prior to forwarding the firstrequest to the storage device.
 7. A data storage system, comprising: astorage device configured to perform snapshot operations; and a firstcomputing device in communication with a second computing device and thestorage device, wherein the first computing device is configured to:receive a first request to perform a first snapshot operation, the firstsnapshot operation to be performed on a first data set associated withone or more software applications executing on the second computingdevice, forward the first request to the storage device, wherein thestorage device performs the first snapshot operation on the first dataset in response to receipt of the first request, receive a firstidentifier associated with the first snapshot operation, and forward thefirst identifier to the second computing device.
 8. The system of claim7, wherein the second computing device is configured to communicatedirectly with the storage device for a first set of one or more storageoperations and communicate with the storage device via the firstcomputing device for a second set of one or more storage operations. 9.The system of claim 8, wherein the first set includes reading data fromthe storage device and the second set includes one or more snapshotoperations.
 10. The system of claim 7, wherein the second computingdevice is not in direct communication with the storage device and isonly in indirect communication with the storage device via the firstcomputing device.
 11. The system of claim 7, wherein the secondcomputing device does not have direct access to the storage device andonly indirectly accesses the storage device via the first computingdevice.
 12. The system of claim 7, wherein the first computing device isfurther configured to receive snapshot operation requests from aplurality of other computing devices and forward the snapshot operationrequests to the storage device.
 13. The system of claim 12, wherein thefirst computing device authenticates with the storage device prior toforwarding the snapshot operation requests.